activity 2 3 2 tensile testing with the ssa

Activity Activi ty 2.3.2 Tensile Testing – SSA Introduction Tensile testing provides engineers with the ability to verify and establish material properties related to a specific material. This verification process is critical in insures the selected material will meet design specifications. In this activity you will interpret and make sample specific calculations related to the material properties of a dog bone test sample.

Equipment Dog bone test sample SSA 1000 Tensile Tester  omputer with SSA 1000 Software Dial aliper  !ermanent "arker  Material Testing Formula Sheet

rocedure 1. Identi Identify fy test test sample sample mater material ial type type

#$$$$ #$$$$$$ $$$ $ ar arbon bon Steel Steel$$$ $$$$$  $$ 

%. &sing &sing a dial dial calipe caliperr measur measure e and and record five diameter measurements of the narrowed dog bone testing region. a. $$$. $$$.0 0'($$ '($$$$ $$$  $  b. $$ .11 .11'$$ '$$

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c. $$$. $$$.0 0'%$$ '%$$$$ $$$  $  d. $$$. $$$.1 11)$$ )$$ $$  e. $$$. $$$.1 101$$ 01$$$$ $$$  $  ). Identify Identify and rerecor rerecord d the the smalle smallest st measurement from the dog bone testing region.

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(. &sing &sing a dial dial calipe caliperr measur measure e and and record the length of the dog bone.

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+. !osition the test sample in the tensile tensile tester as directed directed by your your teacher. teacher. !ro,ect -ead The ay/ Inc. opyright %011 ! 2 &nit % 2 Activity %.).% 2 Tensile Testing 2 SSA 2 !age 1

*. Tensile test test your test test sample as directed directed by your your teacher. teacher. 3. !ositio !osition n your your broken broken dog bone bone broken end to end. 4. &sing &sing a dial dial calipe caliperr measur measure e and and record the length of the dog bone.

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'. &sing &sing a dial dial calipe caliperr measur measure e the the diameter of the necking region of  the dog bone test sample

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10.alculate the test samples total Strain5Deformation 2 The total amount of elongation of a sample to rupture normali6ed 7divided8 by the initial length.

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total

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total

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εtotal 9 .004 11. alculate the test samples ductility: The ability of a material to be deformed plastically without rupture. ( o) Elongation  ! εtotal *%$$+

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; of longation 9 .4; 1%.alculat 1%. alculate e the test samples reduction in area eduction in area ar ea ! *A * A original – A )inal+"A original-%$$ original-%$$  A .0(*?% ).1(>.0(*?% 9.00** 9.00**  A @IA-9).1(>.00 @IA-9).1(>.00)3+?%9.0 )3+?%9.0000(( 000((


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1).reate a print screen of your completed tensile test and insert the graph into the test sample calculations tables.

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Test Test sample calculations roportional #imit Stress The greatest stress that a material is capable of withstanding without deviation from straight line proportionality between the stress and strain. If the force applied to a material is released/ the material will return to its original si6e and shape.

Tensile test results graph 7Insert test graph8

!roportional limit

-ocate the proportional limit on the test graph. Solve for the proportional limit stress# σ 9 !5A )115.00**9 )115.00**9 (31%1.%1 (31%1. %1

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 1ield oint Stress The point at which a sudden elongation takes place/ while the load on the sample remains the same or actually drops. If the force applied to the material is released/ the material will not return to its original shape.

Tensile test results graph 7Insert test graph8 Bield !oint

-ocate the Bield !oint on the test graph.

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ltimate"Tensile ltimate"Tensile Stress The point at which a maCimum load for a sample is achieved. eyond this point elongation of the sample continues/ but the force eCerted decreases.

Tensile test results graph 7Insert test graph8 <imate5 Tensile Tensile stress str ess

-ocate the maCimum load location on the test graph. Solve for the <imate5Tensile stress# σ 9 !5A

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 rea4ing"upture oint The maCimum amount of stress that can be applied before rupture occurs. The specimen fractures in the necking region where the material reduces in diameter as it elongates.

Tensile test results graph 7Insert test graph8

reaking !oint

-ocate the reaking5
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 Modulus o) Elasticity  A measure of a materialEs materialEs ability ability to regain regain its original dimensions dimensions after the the removal removal of  a load or force. The modulus is the slope of the straight line portion of the stress: strain diagram up to the proportional limit.

Tensile test results graph 7Insert test graph8

"odulus of lasticity 7Slope of line8

 "* Solve for the "odulus of lasticity# E ! *%/2+#$ "*

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 Modulus o) esilience  A measure of a materialEs materialEs ability ability to absorb absorb energy energy up to the elastic elastic limit. limit. This modulus is represented by the area under the stress vs. strain curve from 0:force to the elastic limit.

"odulus of
Tensile test results graph 7Insert test graph8

Identify the "odulus of
 ! 5* Solve for the "odulus of
yp

+

 yp

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 Modulus o) Toughness Toughness  A measure of a materialEs materialEs ability ability to plastically plastically deform without without fracturing. fracturing. ork is performed by the material absorbing energy from the blow or deformation. This measurement is eFual to the area under the stress vs. strain curve from its origin through the rupture point Tensile test results graph 7Insert test graph8

"odulus of Toughness 7Total area under the curve8

Identify the "odulus of Toughness on the =raph

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