An Introduction to Aerospace Aerospace Composite Manufacturing Technology Greg Hasko Applications Engineer Connecticut Center for Advanced Technology
[email protected]
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Aerospace Composite Manufacturing Assessment
Introduction This document is intended to be an introduction to the various processes used in manufacturing structural composites for aerospace. We review the raw materials, materials, primary and secondary manufacturing methods, inspection, emerging methods, and software tools that enhance the flow f low of information between design, analysis and manufacturing. manufacturi ng. Links are provided to the sources in each of the topics covered. covered. This document document will be updated on at least an annual basis.
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Contents
page Part Characteristics – Characteristics – Airframe vs Engine
4
Raw Materials – Materials – Fibers, Matrices, Inserts
6
Manufacturing Methods – Methods – Shaping and Curing
11
Material Formats
19
Processes & Equipment
25
Emerging Methods
63
Software Softwar e Tools Tools – – Design, Analysis, Manufacturing
71
National Resource Centers
83
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Typical Airframe Part Characteristics
• Large Large dimens dimension ions; s; sever several al feet feet to 10‟s 10‟s of feet. feet.
• Low to medium contour. • Mostly moderate temperature environment. • Need damage tolerance. • Some need anti-ice. • Mostly one part / per part-number / per vehicle.
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Typical Engine Part Characteristics
• Smaller dimensions; several inches up to several feet.
• More severe contours. • Temperatures can go beyond polymer matrix capability. • Need damage tolerance, erosion resistance.
• Some need anti-ice. • Can have multiple parts / per part-number / per engine.
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Composite Structures are Created by Combining the following Materials • Fibers • Matrix • Cores and Inserts • Adhesives
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Fiber Materials • Aerospace parts are made from a few types of fibers. • They vary widely in density, density, mechanical properties and cost. c ost.
• If not planned carefully, fiber deposition can add high labor costs. • The thermal expansion needs to be accounted for in tool design. Density [Lb/in3]
max use temp [F]
modulus [MLb/in2]
strength [KLb/in2]
[x10-6 in/in/F]
CTE
Fiberglass [two types]
.091
700
10-13
500-650
3
Aramid [multiple brands]
.052
500
17
400
-3.5
Graphite [many types]
.063
1000
33/43/64+
300-800+
-.05
Silicon Carbide
.090
2400
28
400
2
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Matrix Materials • Aerospace parts are made with several types of matrix materials. • They vary widely in temperature resistance, processing characteristics and cost. Density [Lb/in3]
max use temp [F]
modulus [MLb/in2]
strength [KLb/in2]
CTE [x10-6 in/in/F]
Epoxy
.046
200
0.5
10
40
Bismaleimide [BMI]
.046
300
0.7
15
40
Polyimide
.052
500+
0.5
10
25
Polyethersulfone [PES]
.049
350
.4
12
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Polyetherether-ketone [PEEK]
.048
250
0.5
15
25
Carbon
.063
3000+
1-2
1
1-2
Ceramic
.090
2000+
10
10
2
.10-.16
1000+
10-17
20-100
5-12
Metal
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Cores & Inserts • Aerospace parts parts are frequently frequently made in a sandwich sandwich construction of composite skins with low density cores. • Local inserts are used for strength at joints. Density [Lb/ft3]
max use temp [F]
Fiberglass/phenolic honeycomb
3-8
500
Aramid/phenolic honeycomb honeycomb
2-9
350
2-19
300
40
200-450
95-173
200-600
Foam, closed cell, PMA Syntactics [glass spheres in resin matrix] Solid Laminated or Metallic Core Inserts Inserts
Metallic fasteners with special features for strong joints in composites, typically bonded in place.
Functional Materials
Various materials are being embedded to enable structural health monitoring and actuation.
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Adhesives There is a wide variety of adhesives used in aerospace structures, available in several compositions and forms.
Form Paste
Characteristics Usually a 2-part system that is mixed just prior to application. Some cure at room temperature, some at elevated temperature.
Film
Thin films supplied on rolls, and must be refrigerated. They can be cut and applied in selected patterns. They require heat to cure.
Foaming
These are pastes that foam upon cure, to fill hollows in a part or to splice edges of honeycomb cores.
Powder Tackifier
Nano Additives
Usually a version of the matrix resin that is applied to dry fabric used for RTM parts. parts. The powder is used to provide tack to hold plies together during preforming steps. It should not detract from the cured mechanical properties. A wide variety of materials and forms take advantage of the unique properties at the nanometer level. level. Order-of-magnitude increases are possible in mechanical and electrical properties of matrix resins, adhesives and coatings. 10
Composite Manufacturing Methods
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Manufacturing Methods There are two main approaches for manufacturing of composites, based on whether the resin is introduced before or after shaping the fibers. • Choices made in the design of a part influence which branch is followed, and the types of processes and equipment that are used. • Cost-effective parts need to be designed with a knowledge of the processes involved. • Repeatable quality and cost are achieved by properly pr operly specifying all parameters. SHAPING
RESIN
FIBER
CURE RESIN
SHAPING
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Manufacturing Methods Another way to classify manufacturing processes is by the shaping and the curing methods.
Shaping Fabric, Manual • Prepreg or, w/ Tackifier • Stitching Machine • Filament Wind • Braid • 3D Weave • Pultrude • Stitching + fixtures • Automated Fiber Placement
Curing - Heat & Presure • Self-Contained Mold • Press • Autoclave/Vacuum Bag • Oven/Vacuum Oven/Vacuum Bag • Electron Beam/Vacuum Bag • Pultrusion
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Resin Applied Prior To To Shaping [Prepreg Material] The typical sequence for these types of processes:
AUTOMATED AUTOMATED FIBER PLACEMENT RESIN
FILAMENT WIND
AUTOCLAVE AUTOCLAVE MOLD
ROLL WRAP
RESIN
PULTRUDE
DRY FIBER TOW
AUTOCLAVE AUTOCLAVE MOLD 2D WEAVE
RESIN
CUT
LAYUP COMPRESSION MOLD
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Resin Applied After Shaping [Dry Material] The typical sequence for these types of processes: RESIN
FILAMENT WIND/ BRAID
OVEN
RESIN
DRY FIBER
PULTRUDE RESIN
2D WEA WE AVE/BRAID* CUT 3D WEA WE AVE/BRAID*
PREFORM
RESIN TRANSFER MOLD*
*There are many variations of these processes
OVEN, PRESS
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Design / Manufacturing Information Flow Information flow is as important as material flow. Machine-specific software for cutting plies Structural FEA Model Cutting File Process FEA Models [emerging]
3D CAD Model
Bill of Materials
Company-wide software for purchasing and scheduling
Ply shapes & s/n‟s Sequence of Operations Drawing
Documentation for technicians
Process Specifications Ply s/n
Ply orientation
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Finished Part Manufacturing Methods Method
Guidelines
Manual Layup / Resin Transfer Mold
• All All surfaces are tooled
Manual Lauyp / Compression Mold
• All All surfaces are tooled
Manual Layup/Autoclave Mold
•Usually one surface is tooled, but can add caul sheet on opposite side
Airframe Engine X
X
•Good for multi-hollow parts X
•Practical size limited by press capacity X
X
•High capital and operating costs Automated Fiber Placement/ Placement/ Autoclave Mold
•High deposition rates
Filament Winding, Braiding
•Variable cross section
X
• Allows Allows continuous fibers over large areas X
•Minimal labor Roll Wrapping
•High Rate
X
•Circular sections, tapered Pultrusion
•High rate, constant cross section
X
•Minimal labor Machining
•Need special bits, settings, coolant •Can use ultrasonic, laser and waterjet
X
X 17
Common Needs for All Manufacturing Approaches
1. Tooling – to deliver an accurate shape after cure.
2. Accu Accura rate te fib fiber er pla place ceme ment nt – – alignment within 2° of nominal, uniform spacing, no wrinkles. 3. Comp Comple lete te res resin in int intro rodu duct ctio ion n – no dry spots, typically 40 – 40 – 50% by volume. 4. Air re removal – minimal void content, below 2%.
5. Compaction – for good strength-to-weight strength-to-weight ratio, need from 14 to 150 psi. 6. Cure – needs to be above the maximum service temperature. 7. Finishing Finishing operations: operations: machining, machining, bonding, bonding, coating. coating.
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Material Formats
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Typical Characteristics of Prepreg Materials
Resins are applied to single tows that are up to ¼” wide, or to 2D fabrics, that are stored on spools. This process, called prepregging, adds cost but eliminates the need for the part fabricator to worry about resin mixing and resin content. The physics of resin flow into fibers limit the ply thickness that can be made to the range of .005 to .050”. The primary type of resin used in aerospace is thermosetting, has a limited working time at room temperature, and must be stored under refrigeration. Thermoset prepregs are tacky, tacky, which aids laying laying up plies into contoured contoured molds. Thermoplastic prepregs do not need refrigeration, and are not tacky. tacky.
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Typical Characteristics of Dry Fiber Materials
Dry processing uses the lowest lowest cost form of the raw materials. materials. Resin is introduced by the Resin Transfer Molding [RTM] process, or by in-line wetout. The thickness that can can be molded is only limited by the resin characteristics; the flow time before it gels and the threat of exotherm in thick areas. Some resins give off off gaseous byproducts byproducts that need to be removed before cure. Dry fibers are not tacky, tacky, and require binder binder materials or stitching to stabilize complex shapes. Some binders are thermosetting and dissolve into the matrix resin.
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Typical Characteristics of Conventional Fabrics
• Many types; plain, satin, crowfoot, etc. • Widths Widths can be up up to 5‟. 5‟. • Large databases of material properties exist. • The size and type of fiber in each direction can be varied to create hybrids. An extreme case is “uniweave”, with heavy graphite in one direction and fine fiberglass in the other, to approximate prepreg tape.
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Typical Characteristics of Non-Crimp Fabrics • One ply can have multiple layers at different angles, held together by lightweight knitted fiber; can reduce labor content. • Cured laminates have higher properties than conventional weaves. • Widths Widths can be up to 12‟. 12‟.
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Methods to Increase Through-Thickness Properties
To improve impact, strength and thermal properties in the thickness direction, a variety of methods are available: • 3D Weaving & Braiding – Braiding – Jacquard looms, etc • Stitching – Stitching – industrial strength • Z Pins – Pins – small embedded composite pins
3D weaving and braiding also reduce ply layup labor; however the linear production rate is slower than 2D fabrics.
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Manufacturing Processes and Equipment
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Hand Layup
This is the traditional method, needing trained technicians. It can be be done with prepreg and dry material. To form the material around tight contours without wrinkling, relief slits or „darts‟ are cut. Fibers within a ply shear shear and skew as they are placed onto contoured molds. The pattern of darts and the sequence of laying down the perimeter of large plies needs to be repeated from part to part. This method is susceptible to FOD being cured within the laminate; gloves, tape, knife blades, etc.
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Ply Placement Templates and Draping
For repeatability when using hand layup, guides are needed to align ply directions and edges. These guides can be scribe lines on molds, mylar sheets, or fabricated metal or composite templates that pin into location at the edge of the mold. Plies at the edge of a part may have extra tabs designed into the flat patterns to allow verification by an inspector. inspector. These tabs are are trimmed off after after cure.
Note that the weave pattern distorts when placed onto a contoured mold. The hoop strength of the red zone is much different different than the blue zone. The designer must specify the draping method, and this information must be transmitted to the shop floor. See the Software section for packages that can simulate draping.
+/-30°
0/90° 27
CAD-Driven Ply Placement Guides
Laser-Guided Ply Placement
Video-Guided Ply Placement
Projectors that operate from CAD data display ply patterns and fiber angles onto the mold during hand hand layup. layup. Line width width adjustment is needed in highly sloped areas. Tolerance bands can be indicated indicate d in the projected pattern.
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CNC Ply Cutter
These machines are used for dry or prepreg material. Ply shapes are determined manually and scanned into a digital data file, or determined from software that models draping and flattening for contoured shapes. Software is also used to pack the ply patterns efficiently to minimize waste when cutting.
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Braiding Processes Modified „shoelace‟ machines are used, usually with dry fibers. Braided sleeving can be packaged on on a spool for hand layup, or contoured mandrels can be fed through the machine to braid onto the net shape. Braided preforms typically go into an RTM process, although prepreg and in-line wetout have been demonstrated. Large commercial braiders have an approximate 7-foot ID, which can be fully covered with near-hoopwise fibers. However, However, another limit is the diameter that can be fully covered at a given angle with the fiber bandwidth of about .25”. The maximum diameter that that can be fully covered at at a 45 degree angle is 8”. Specialty braiders exist that are almost four times this size. Since all the spools on the machine must pass over and under each other, they are smaller than those on weaving looms. Therefore, reloading time is a factor in i n determining the maximum attainable length length and cost. Typical Typical parts include propeller spars, missile bodies, bushings, accessory beams. 30
Braiding Parameters
0
0
Biaxial
Triaxial
Braiding machines can be set up to deliver one or two sets of fiber; a biaxial set and an axial [0 degree] set. The combination of biaxial and axial is called triaxial. The angle of the biaxial fibers fibers can range from nearly 0 degrees to nearly 90 degrees. Different types and weights of of fiber can be used to create hybrids. The choices of these these parameters depend on the structural and cost requirements. Straight and curved parts can be made by using appropriate mandrel handling devices. The cross-section can not have concave areas, or the fibers fibers will bridge. Severe cross section changes can be accommodated, such as the transition from the cylinder to the flange of a bushing. bushing. The mandrel can be reciprocated back and forth to build up layers. Other fabrics and core materials can be inserted between layers. layers. Removable pins on the mandrel enable net-shaped holes without drilling.
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3D Braiding and Weaving 3D fiber architectures and shaped crosssections [I, T, hollow, etc] are made on braiders that control the motion of every fiber spool. Jacquard weaving looms control the interweaving of each yarn to achieve similar results.
3D Braider Individual yarn controller
3Tex 3Tex I-Beam I -Beam
Jacquard Loom
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Pultrusion Process
Dry fibers are pulled through a resin applicator and a curing die. Shaping and curing occur nearly nearly simultaneously. simultaneously. Typical parts are floor beams and strengthening inserts in wing spars. spars. Entire wing wing sections have been demonstrated. Parts are limited to straight, constant crosssectional shapes. shapes. Parts to several feet in width can be pultruded, given enough pulling capacity. Length is limited only by the creel capacity and take-up provisions. Fabrics, cores and inserts can be incorporated. A variation called Pullforming is used in the automotive industry industry to make leaf springs. Wet fibers are drawn onto a heated rotating mandrel having a shaped cavity.
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Resin Transfer Molding Processes In this process dry preforms are enclosed in a mold, then a thermosetting resin is introduced. introduced. This reduces capital and operating expenses expenses compared to autoclave autoclave curing. Very Very complex parts can be made, such as vane/ring packs. Resin selection is limited to those that have have low viscosity [<1000 cP], for long enough time [typically 1 hour] to complete the injection. There are numerous variations, basically divided into into matched mold and and bag mold methods. There are some similarities to plastic injection molding, but the resin is much lower in viscosity and the cure cycle is much longer than a quick cooling cycle. Part quality is improved with dry nitrogen purging followed f ollowed by vacuum.
RTM Transmission Fitting • Thick-wall graphite composite. • ~20-piece mold was used.
• Final edges were machined.
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Preforming for RTM Processes A binder is applied applied to the fabric fabric before plies plies are cut out. out. Plies are shaped and stabilized on preforming molds, usually with vacuum and some heat, prior to assembly into the RTM mold. This increases preform repeatability and reduces the RTM mold cycle time. Stitching is also used to t o make shaped preforms, and in addition provides translaminar translamina r strength. Fixtures hold the fabric in alignment during the stitching process.
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RTM in a Matched Mold RTM in a matched mold provides an excellent excellent finish on all surfaces. It enables using 3D textile preforms that can not be made by prepreg methods. Parts are typically typically up to a few feet in size. The preform has a great influence influence on the flow flow pattern. The closed mold mold is a pressure vessel [typically 100 to 200 psi], and needs great stiffness to yield parts with uniform wall thickness.
RTM Mold Injector or pressure pot
Vacuum Pump
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Typical Features of RTM Molds
• Inlet and outlet ports – ports – locations optimized to completely fill the preform. • High stiffness to resist preform compaction and resin injection pressures. • Clamps - either around the perimeter, perimeter, or use an external frame or press. • Heating – Heating – can be integrally heated with electric rods, steam, or hot oil, or a press or oven can be used. • Sensors – Sensors – thermocouples and other types to monitor pressure and degree of cure. • Vacuum-tight; O-rings enclose the part cavity. • The mold can have multiple cavities.
• Molds may have over 100 internal pieces, manually assembled. • Trapped mandrels are removed using melt-out or wash-out materials.
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Vacuum Assisted Resin Infusion [VARI] Process
This is done on a one-sided mold, with a vacuum bag on other side. Resin is drawn into the preform with vacuum. A high-flow media can be placed over the preform so that resin quickly spans large parts. The bagged bagged side has has a rougher surface than the mold side after cure. Mechanical properties are typically lower than with an autoclave pressure cure or with matched mold RTM. Parts can be up to 10‟s 10‟s of feet in size.
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Resin Film Infusion [RFI] Process This is a variation of VARI, using a one-sided mold and a vacuum bag on other side. A solid resin film is placed on the mold, then covered with the preform and a vacuum vacuum bag. As this assembly is heated, heated, the resin melts and and flows into the preform under vacuum vacuum pressure. This process can also be done in an autoclave for additional compaction and driving pressure. As with prepreg prepreg and VARI, VARI, the bagged bagged side has a rougher surface than the mold side after cure. Parts can be to 10‟s of feet in size. Vacuum bag Resin melts and flows
Can have very thick preforms Solid resin film Mold 39
RTM Injection Equipment
For VARI processing an open container will suffice, since resin is drawn in with a vacuum pump. pump. For injection injection into a matched matched mold, a pressurized paint pot can be used. Positive displacement pumps enable computerized process control and recording. Meter-mix machines can be used with dual component resins. Most resins need to be heated to t o reduce viscosity, viscosity, so heated chambers and delivery hoses are available.
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Compression Molding Processes
Prepreg materials can be cured in a matched mold as in RTM, giving good surface finish throughout [as opposed to bag methods such as autoclave or VARI]. Maximum size is governed by press capacity, capacity, typically up to several feet. Vacuum is typically not needed. Proper sequencing sequencing of pressure during the heat cycle is critical to making void-free parts with proper fiber alignment. Typical Typical parts are stator vanes.
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Filament Winding Processes This uses a device similar to a lathe. A revolving mandrel is covered with fibers kept under tension. It can be done using inline wetout, prepreg, or dry fiber followed by an RTM cure. Curing is normally normally in an oven. External cauls or shrink wrap film can be used for compaction. Typical Typical parts are pressure tanks and rocket bodies. Since fibers are kept under tension, the cross-section can not have concave areas or the fibers will bridge. They must either lay down in geodesic patterns normal to the local contour, contour, or extra mechanical means such as pins or friction must m ust be used to prevent slipping. These factors must be observed in the design phase. The fiber angle angle can range range from 0 [with appropriate restraints at the ends] to 90 degrees to the rotation axis. Large spools of fiber can be used, as in weaving. Shapes are limited to the number of controlled axes of the machine; slightly tapered straight parts such as truss tubes c an be made on a 2-axis machine, whereas curved parts with closed ends may require 5 axes. Length and diameter can range up to 10‟s of feet. Parts have been made over 100‟ long with over 1” wall thickness.
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Automated Fiber Placement Processes
Automated Fiber Placement [AFP] takes filament winding a step further. further. It uses prepreg prepreg fibers placed onto a contoured mold with a multi-axis head. Fibers are stabilized by the resin tackiness tackiness and contact contact rollers. Labor content is reduced and speed increases compared to hand layup. Typical parts are fuselage and nacelle skins. The size can be 10‟s of feet feet on a side. Both the mold and the fiber placement head are in motion. Individual fibers can be cut and restarted to cover any shape s hape at any angle. As opposed to filament winding, concave features are permissible. Parts are vacuum bagged and cured in an autoclave. See videos: http://www.automateddynamics.com/video_library.php
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Robotic Ply Layup
Special machines have been developed to deposit deposit prepreg fabric. They can lay fabric on a mold and trim the edge. They are used for mildly contoured c ontoured shapes such as wing skins.
A variation is to use a “pick and place” robot to stack pre-cut plies on a mold.
Broetje pick and place robot
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Tube Rolling Table
Prepreg is rolled onto a mandrel and cured in an autoclave, or shrink wrapped for an oven cure. Mandrels must be straight and circular, but can be tapered or stepped. Tables typically typical ly are designed for parts up to 10‟ length and up to 6” diameter. diameter. Typical Typical parts are truss tubes.
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Autoclaves
Heated pressure vessels are normally used to cure prepreg prepreg materials. They can be 10‟s of feet in diameter and length. One-sided molds are normally used, and several parts that have the same resin can be cured together. together. Resin Film Infusion into dry preforms has been demonstrated on large parts having translaminar reinforcement.
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Heated Press
Used for compression molding and RTM. Heat is supplied by electric cal rods or an oil system. Presses typically have one axis of motion for slightly contoured parts, but custom presses have been built with multiple axes.
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Ovens
Ovens can be 10‟s of feet in length, width and height. They may have a rotisserie for filament wound parts, to avoid resin pooling. pooling. They are used for heating bolted RTM molds or vacuum-bagged VARI molds. Heating can be electric, gas or oil. The floors may need to withstand multi-ton molds.
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Inspection Methods, In-Process and Post-Cure This is a dynamic, rapidly evolving area that entails a variety of physical principles. In-process checks are done to verify proper ply sequence, ply angle, and ply edge location. Post-cure inspections check for non-desirable items such as wrinkles, voids, delaminations, and embedded foreign objects. In some methods the structure is passive, with defects creating a disturbance to an applied applied signal. In others the structure is mildly mildly disturbed with heat or a mechanical load, and the surface is scanned for indications that print through.
Sonatest Wheelprobe Acousticam
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Machining
The tool bits, feeds, speeds and coolants used to machine composites are specific to the matrix and fiber combination. Excessive heating causes polymeric resins to decompose. Improper cutting tools can pull fibers out of the resin locally. locally. Lasers and waterjets are used, especially on ceramic matrix composites where the part is made out of similar materials as the cutting tools themselves. Trim & Drill Fixture
Residual stresses locked into the part during cure can cause parts to deform or delaminate during machining.
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Bonding Fixture
Custom-designed fixtures are used to hold parts accurately and maintain bondline thickness despite thermal expansion effects. They can be self-heated or used in an oven. For quality quality control they are instrumented with thermocouples.
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Composite Manufacturing Related Companies
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Finished Part Manufacturers This is a partial list of aerospace manufacturers by process type. For a more extensive list see sources such as the annual Composites World Sourcebook [www.compositesworld.com/ [www.compositesworld.com/]. ]. Method Manual Layup / RTM
Manual Lauyp / Compression Mold
Company
Web site
V Systems
www.vsc-inc.com
ITT Integrated Structures [ex Fiber Innovations]
www.defense.itt.com
AAR Composites
www.aarcorp.com/composites
Albany Engineered Composites Composites
www.albint.com/aec
GKN-CT/AL/St Louis
www.gknaerospace.com
Cobham [ex Sparta]
www.composites.sparta.com
North Coast
www.northcoastcomposites.com
GKN-CT/AL/St Louis
www.gknaerospace.com
CTL Aerospace
www.ctlaerospace.com
CHI
www.chi-covina.com
Matrix
www.matrixcorp.com
Cobham [ex Sparta]
www.composites.sparta.com 53
Finished Part Manufacturers
method
company
Manual Layup/
Spirit Aerosystems
www.spiritaerosystems.com
Autoclave Mold
GKN-AL
www.gknaerospace.com
ITT Integrated Structures
www.defense.itt.com
Vermont Vermont Composites
www.vtcomposites.com
V Systems
www.vsc-inc.com
Hexcel
www.hexcel.com
Kaman
www.kamanaero.com
Matrix
www.matrixcorp.com
Cobham [ex Sparta]
www.composites.sparta.com
Tighitco
http://www.tighitco.com/
Filament Winding
Lincoln
www.lincolncomposites.com
Pultrusion
Kazak
www.kazakcomposites.com
Automated Tow Tow Placement/ Autoclave Mold
Vought
www.voughtaircraft.com
ATK ATK
www.atk.com
Hitco
www.hitco.com 54
Finished Part Manufacturing Technology Technology Providers This is a partial partial list of equipment equipment manufacturers by equipment equipment type. For a more extensive list see sources such as the annual Composites World Sourcebook [www.compositesworld.com/ [www.compositesworld.com/]. ]. Method Compression Molding Press
Autoclave
Automated Fiber Placement Machine
Equipment Maker Wabash
www.wabashmpi.com
Pacific Press
www.pacific-press.com
Technical Machine Products
www.techmach.com
Tarrico
www.tarrico.com
American Autoclave
www.americanautoclave.com
ASC Process Systems
www.aschome.com
MAG Cincinnati
www.mag-ias.com
Ingersoll
www.ingersoll.com
Automated Dynamics Dynamics
www.automateddynamics.com
Electroimpact
www.electroimpact.com
Accudyne
www.accudyne.com 55
Finished Part Manufacturing Technology Technology Providers
Method Filament Winder Oven Robotic Ply Layup
Equipment Maker Entec
www.entec.com
McClean Anderson
www.mccleananderson.com
Wisconsin
www.wisoven.com
Grieve
www.grievecorp.com
Composite Systems
www.compositemfg.com
Diaphorm
www.diaphorm.com
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Ancillary Manufacturing Methods This is a partial partial list of equipment equipment makers by equipment equipment type. For a more extensive list see sources such as the annual Composites World Sourcebook [www.compositesworld.com/ [www.compositesworld.com/]. ]. Equipment Makers Ply Projection
Ply Cutters
RTM Injectors
Non-contact Dimensional Measurement
Virtek
www.virtek.ca
LAP Laser
www.lap-laser.com
Anaglyph
www.anaglyph.co.uk
Laser Projection Technologies
www.lptcorp.com
Assembly Guidance Systems
www.assemblyguide.com
Gerber
www.gerbertechnology.com
American GFM
www.agfm.com
Eastman
www.eastmancuts.com
Radius
www.radiusengineering.com
Graco/Liquid Control
www.graco.com
Stienbichler
www.steinbichler.de
Creaform
www.creaform3d.com
Twin Coast
www.twincoastmetrology.com
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Inspection Methods
Equipment Makers Laminate NDI
• Physical Acoustics - Acoustic Emmission
www.mistrasgroup.com
• Imperium - Digital Acoustic Video
www.imperiuminc.com
• A2 - Exoscan handheld FTIR
www.a2technologies.net
• Evisive - Microwave Scanning
www.evisive.com
• LSP Technologies Technologies - Laser Bond Inspection
www.lsptechnologies.com
• Photo Emission Tech Tech - UV Surface Excitation
www.photoemission.com
• Advanced Structural Imaging - Computer-Aided Tap Test Test
www.asi-nde.com
• Boeing - Mobile Automated Automated Ultrasonic Scanner [MAUS]
www.boeing.com
• Digiray - Motionless Laminography X-Ray
www.digiray.com
• Steinbichler - Laser Shearography
www.steinbichler.de
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Inspection Methods
Equipment Makers Laminate NDI
• Laser Technology Technology - Laser Shearography
www.laserndt.com
• Thermal Wave Imaging - Pulsed Thermography
www.thermalwave.com
• Wichitech - Electronic Digital Tap Tap Hammer
www.wichitech.com
• Quality Material Inspection - Air-coupled Ultrasound
www.qmi-inc.com
• Honeywell International - Structural Anomaly Mapping System [SAM], acoustic/laser
www.honeywell.com
• Lockheed - Laser Ultrasonic Technology Technology
www.lockheedmartin.com
• PaR Systems - Laser Ultrasonic Technology Technology
www.par.com
• iPhoton - Laser Ultrasonic Technology Technology
www.iphoton.com
• Mitsui Engineering - Woodpecker automated tap tester
www.mes.co.jp
• Sonatest - Ultrasonic wheel probe array
www.sonatest.com
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Precursor Manufacturing Technology Technology Providers This is a partial partial list of manufacturers manufacturers by material type. For a more extensive list see sources such as the annual Composites World Sourcebook [www.compositesworld.com/ [www.compositesworld.com/]. ].
Equipment Makers
Equipment Users
Uniweave, Dry & Prepreg
Western Advanced Engineering
Hexcel, Cytec, Nelcote, APCM, YLA
Plain & Satin Weave, Dry & Prepreg
numerous
Textile Products Inc, Hexcel
Braid, Dry
Wardwell, Steeger, Steege r, Hacoba, Herzog
ITT, ITT, A&P, A&P, Bally Ribbon, Albany Techniweave, Fabric Development
Non Crimp Fabrics
Liba, Malimo, Mayer
Saertex
Filament Wind
Entec, McClean Anderson
Lincoln
3D Weave
3TEX
3TEX, Bally, Bally, Fabric Development, TEAM, Albany Techniweave
Stitched Fabrics, Dry
Puritan
Boeing
Z-pins, Prepreg Prepre g
Albany Techniweave echniwea ve
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Issues With Manufacturing Processes Activity
Issues
Ply Layup & Forming
• Need automation; constitutes large portion of part fabrication labor.
Part Trimming Trimming
• Labor content and accuracy can be improved by multiaxis CNC.
Nondestructive Evaluation • Laminate integrity
• Need a nondestructive method to verify ply angles and ply boundaries.
• Cure state
• Need NDI instruments that can reach into tight spaces.
• Ply Angle Verification, Post-Cure
• Need to map defects into 3D CAD files.
Physics-Based Process Simulations
• Need software to be more user-friendly for front-line engineers.
• RTM – RTM – avoid dry spots, resin racetracking, local exotherm • Compression Molding – Molding – avoid „horsetails‟ expelled from mold
• Need to quantify material processing parameters accurately.
• Autoclave Flow – Flow – ensure thermal uniformity with an arbitrary loading of parts Mold Design for In-tolerance Parts
• Use physics-based design tool to account for warping [see Convergent Manufacturing Technologies, Technologies, Inc]. • Need to quantify material parameters accurately.
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Issues With Manufacturing Processes Activity
Issues
Molecular Sensors For Process Control.
• Better control than a canned time/temperature profile.
•fiber optic
• Need user-friendly systems to install in production molds.
•dielectric
• Need accurate material characterization. • Need affordable systems. Prepreg Perishability
is being applied to • Avoid manual data logging. RFID is insure that material is used on time.
Out-of-Autoclave Curing
• Reduce energy consumption and capital expense of pressure vessel. • Need materials designed for vacuum-only cure cycles.
Resin Cure Time
• Resins typically need multi-hour cure cycles. This requires multiple molds and curing systems for highrate production.
RTM with Intractable Resins
• High viscosity, viscosity, short shor t pot life • Advanced cure cycles – cycles – sum up the viscosity dips • Port configuration – configuration – thru-thickness flow • Combination - sequential sequential porting
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Emerging Methods for Composite Manufacturing
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Emerging Manufacturing Technology Roctool Inc
Rapid heating by an array of induction heads.
http://www.roctool.com/ Quickstep Inc http://www.quickstep.com.au/what-isquickstep 2PHASE Inc http://www.2phasetech.com/ Electron Beam Curing www.ebeamservices.com
Applies heat and pressure by liquid instead of gas for quicker heat transfer. Reconfigurable mold surface for rapid prototyping pr ototyping or repairs. Quick cure without thermal effects. Need radiation shielding and resins designed for this process
www.acsion.com 3D Shape Weaving [Shape3 Inc]
Seamless net-shape preforms; no cut fibers.
http://www.shape3.com/ P4 Process
Discontinuous fibers applied onto molds in controlled http://www.compositecenter http://www .compositecenter.org/index.php/r .org/index.php/r patterns to avoid manual ply layup. apid-fiber-preform.html Out-Of-Autoclave processes http://www.advancedcomposites.co.uk/PSG_Electronic_Files/A erospace_PSG_Files/outofautoclave.html
Prepreg materials are being developed to enable curing and acceptable properties without the capital investment for an autoclave. 64
Roctool
Induction heating is used to selectively heat the mold for rapid cycling and low energy use compared to conventional heating. This is used for RTM with with dry preforms and compression molding with prepregs. Size: custom-designed.
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Quickstep Molding System Controls This is a self-contained molding system with a rapid heatup/cooldown system. Molds float in a liquid media, so molds require less stiffness than in other cure processes. It can be used for bagging bagging processes such as autoclave/prepreg, VARI and RFI. Size: up to 20 sq yd area.
Tanks for liquid pressure and heating media
Mold
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Reconfigurable Mold, 2Phase, Inc
This is a reconfigurable mold that uses a liquid/particle media contained by a membrane that solidifies against a master shape. The media media can be re-liquified re-liquified and re-solidified, and can potentially be sculpted to net shape with a CNC machine. Molds up to several feet on a side by 2 feet deep have been delivered.
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Net-Shape Weaving
Net shape contoured weaving has been demonstrated by Shape3, but has not been in high rate production. product ion. To cure the final composite a process such as VARI VARI would be used. http://shape3.com/
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Electron Beam Curing
Composites are cured without heat in a radiation-shielded accelerator. accelerator. The beam is scanned over the entire part. Only resins designed for e-beam cure can be used. Molds can be made made from wood or rigid foam. •see www.acsion.com
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Discontinuous Fiber Preforming, P4 Process
Chopper/sprayer
Chopped, tackified fiber is sprayed onto a porous vacuum form with with a CNC robot. The
preform then goes into an RTM mold for resin injection and cure. This reduces labor content and increases deposition speed compared to hand layup. Somewhat lower mechanical properties result than with continuous fibers. Vacuum mold
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Composite Manufacturing Process Design and Modeling Software Solutions
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Composite Processing: Steps & Simulations Simulation tools are becoming available to assist manufacturing engineers. Heat Resin
Orient Fibers
reaction kinetics
draping tow placement nesting
Resin Flow
thermal & chemical eq's
Mix Resin
geometry & motion
reaction kinetics chemical eq's
Raw Materials
reaction kinetics heat flow viscosity kinetics fiber compaction geometry, geometry, coupled diff e's, molecular mobility sensing
Resin Cure
COTS Software Into Service
reaction kinetics Heat flow CTE build Tg build modulus build resin bulk shrinkage geometry, geometry, coupled diff e's
Design intent achieved
Demold Machining remove material relieve stress residual deformation geometry, geometry, coupled diff e's
remove constraints relieve stress residual deformation
Cooldown residual stress buildup geometry, geometry, coupled diff e's
geometry, geometry, coupled diff e's
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CAD Tools
Not all CAD tools can easily handle composite ply information. Here are some that do:
Features
Web Site
Has fabric draping features and micromechanics calculator. calculator.
www.plm.automation.siemens.com
CATIA
Dassault product, has fabric draping, integration between design/analysis/ manufacturing.
www.3ds.com
Pro-E
Sister product is Pro Mechanica FEA.
www.ptc.com
NX [formerly UG]
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Structural Finite Element Analysis Software Features
Web Site
General purpose, has composite elements
www.ansys.com
General purpose, has composite elements
www.mscsoftware.com
General purpose, has composite elements. Affiliated with Dassault/CATIA.
www.simulia.com/products/abaqus_fea
MARC
Good for nonlinear materials
www.mscsoftware.com/products/marc.cfm ?Q=131&Z=396&Y=400
Pro-E/
Sister product of Pro-E, has composite laminate features
www.ptc.com/products/proengineer/advan ced-mechanica
LS-DYNA
Impact & crash simulation
www.lstc.com/lsdyna.htm
Lusas
General purpose, has composite elements
www.lusas.com/products/composite
Specialized package for repairs
http://www.fea-llc.com/
Has composite laminate features
www.esrd.com
ANSYS NASTRAN ABAQUS
Mechanica
ARPPAS ARPPAS StressCheck
www.plm.automation.siemens.com
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CAD & FEA Translators Due to the large number of software packages and vendors on the market, there is an industry industry issue of file compatibility and interoperability interoperability.. Supply chain companies frequently encounter errors when converting surface and mesh data from customers, needing time-consuming repairs before proceeding with the value-added tasks at hand. Tools exist to ease file translations translations between CAD and FEA formats. Some are listed here: Features Altair - Hypermesh
Web Site
CAD defeaturing and repair, mesh generation
http://www.altairhyperworks.co m/Product,7,HyperMesh.aspx
Elysium - CADdoctor
CAD defeaturing and repair
http://www.elysiuminc.com/
Anark
convert and transform 3D CAD and related product information
http://www.anark.com/
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Examples of Mold Flow Simulation
Vacuum Infusion
• How much time will it take to fill? • Will gravity affect the fill process?
Matched Mold Injection • Where should the runners be placed?
• How much pressure will it take to fill?
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Finite Element Based Process Simulation Tools Physics-based models can be applied applied to arbitrary shapes. shapes. Proper simulation requires that the processing properties of the materials be quantified in the code. Type
Features Feature s
Web Site
RTM Flow PAM-RTM
Resin flow, fabric draping, draping , reacting react ing resin, transient heating.
www.esi-group.com/products/compositesplastics/pam-rtm
LIMS
Resin flow
www.ccm.udel.edu/Pubs/techbriefs/LIMS.pdf
RTM-Worx
Resin flow
www.polyworx.com
Composite Cure Springback COMPRO
Plug-in to ABAQUS and MARC, calculates residual stresses and springback due to resin cure.
www.convergent.ca/products/compro%203d/ overview.html
Point solutions for resin cure can be obtained using their Raven package. 77
Example of Springback Simulation • Composite resins shrink much more than the fibers when curing. • Thermal expansion of some mold materials is much different than the composite. • When a simple 0/90 ply layup is molded on a flat plate, the cured part springs into a curved shape.
90° ply 0° ply Flat mold
• This behavior can require remachining the mold after the first part is made and measured.
• Simulations can be done to account for this; to design the mold surface properly in the first place. 78
Fabric Draping and Flat Patterns A unique feature of composite fiber plies is that they shear and skew as they are placed placed onto a contoured mold. Since fiber angles angles drastically affect mechanical and processing properties, both the designer and the manufacturer need to specify and control this behavior. behavior. The flat cutting patterns depend depend on the draping behavior behavior.. Software packages exist to plan the plies correctly. correctly.
Fibers at B are highly skewed on the mold
B B
A
Draped on Hemisphere
A Flat Pattern 79
Process Simulation S imulation Software Tools Geometry-based tools can be applied to neutral CAD CA D surfaces and FE meshes. Type Type
Features
Web Site
Fabric Draping and Flat Patterns Fibersim
Plug-in to NX, CATIA, CATIA, Pro-E.
www.vistagy.com
Laminate Laminat e Tools Tools
Stand-alone CAD/FEA interface for composite plies.
www.anaglyph.co.uk
Simulayt
Plug-in to CATIA/ABAQUS. CATIA/ABAQUS.
www.simulayt.com
PAM-RTM/Quickform AM-RTM/Quick form
Part of PAM-RTM.
www.esigroup.com/products/compositesplastics/pam-rtm
Interactive Drape
Interactive, inexpensive fabric draping www.interprot.com/ simulator.
Patran/Laminate Modeler
Has fabric draping function.
www.mscsoftware.com
European effort to model fabric unit cells, fabric draping, RTM flow and structural response.
www.itool.eu
‘Soup to Nuts’
ITOOL
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Process Simulation S imulation Software Tools
Type
Features Feature s
Web Site
Filament Winding Entec
Models tensioned fibers on a rotating mandrel.
www.entec.com/
CADWIND
Models tensioned fibers on a rotating mandrel.
www.material.be/filament-windingsoftware
Auto Tape Laying, Auto Fiber Placement Vericut
Can model various machines.
Fiber Placement Expert System
Can model various machines.
ACES
By MAG Cincinnati for their machines.
www.cgtech.com www.compositepro.com/Fipes.html http://cinmach.magias.com/products/automatedcomposites-processing/aces
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Laminate Property Calculation
Features
Web Site
Composite Pro
Calculator to determine stiffness properties of laminates, and structural response of simple shapes.
www.compositepro.com
Helius
Calculator to determine stiffness properties of laminates. Will be adding textile composites.
www.fireholetech.com
Texcad, mmTexlam
Calculator to determine stiffness properties of textile composites.
ITOOL
Determine stiffness properties of textile composites
www.itool.eu
Hypersizer
Calculator to determine stiffness properties of laminates, and structural response of simple shapes.
www.hypersizer.com
Sysply
Calculator to determine stiffness properties of laminates
www.esigroup.com/products/compositesplastics/sysply
K. Shivakumar [
[email protected]] [
[email protected]]
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Composite Materials Resource Centers
Connecticut Center for Advanced Technology Technology
www.ccat.us
University of Delaware Center for Composite Materials
www.ccm.udel.edu
University of Dayton Dayton Research Institute
www.udri.udayton.edu
Air Force Research Lab, Lab, Materials Directorate
www.wpafb.af.mil/afrl/rx
NASA, Langley & Glenn Research Centers
www.nasa.gov/centers/langley/home/inde www .nasa.gov/centers/langley/home/index x www.nasa.gov/centers/glenn/home/index
National Composite Center
www.compositecenter.org
Composites Manufacturing Technology Center
http://cmtc.scra.org/about_cmtc.shtml
National Institute for Aviation Research
www.niar.wichita.edu/researchlabs/comp_ov erview.asp
National Center for Manufacturing Sciences
www.ncms.org
Composites Manufacturing Technology Center
http://cmtc.scra.org/tcc_overview.shtml
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Composite Materials Associations & Publications P ublications Composites World Magazine
Covers a wide range of design/analysis/manufacturing topics. Publishes annual supplier listing.
www.compositesworld. com/
Journal of Composite Materials
Peer-reviewed academic journal.
American Society for Metals
Publishes detailed handbooks on various materials. For composites see ASM Handbook Volume 21.
asmcommunity.asminte rnational.org/portal/site/ www/
Society for the Advancement of Material and Process Engineering
Conducts annual conferences on composite properties, design and fabrication.
www.sampe.org
Society of Manufacturing Engineers/Composites Group
Conducts annual conferences on tooling and manufacturing
www.sme.org
Consortium for Improving/Integrating Advanced Composites Composites Processes (CIACP)
Brings together design and manufacturing technologies.
www.agfm.com/Initiativ es/CIACP.htm
American Society for Composites
Promotes the exploitation of the unique properties of composite materials in emerging applications.
http://jcm.sagepub.com
Conducts regional conferences. www.asccomposites.org
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