2. A polymer muterial is subjected to a constant load for a set amount of time and then the load is removed. This experiment generates the stress versas time plot and the strain versus time plot shown below. Describe what is happening to the material at following locations on the strain versus time plot below: • At point A • Between point A and point B • Between point B and peint C • Between point C and peint D Briefly comment on how you would expect this strain versus time plot to change if the experiment was carried out en anather sample of the same polymer at a temperature below the polyrmer's glass transition temperature. Time, t в A D Time, t Strain, ɛ Stress, o

2. A polymer muterial is subjected to a constant load for a set amount of time and then the load is removed. This experiment generates the stress versas time plot and the strain versus time plot shown below. Describe what is happening to the material at following locations on the strain versus time plot below: • At point A • Between point A and point B • Between point B and peint C • Between point C and peint D Briefly comment on how you would expect this strain versus time plot to change if the experiment was carried out en anather sample of the same polymer at a temperature below the polyrmer's glass transition temperature. Time, t в A D Time, t Strain, ɛ Stress, o

Materials Science And Engineering Properties

1st Edition

ISBN:9781111988609

Author:Charles Gilmore

Publisher:Charles Gilmore

Chapter6: Introduction To Mechanical Properties

Section: Chapter Questions

Problem 6.2P

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Time len A material has the stress-strain behavior shown in the Figure below. Calculate the toughness (T) of this material. given that S1=195 Mpa; S2=243.75 Mpa; El=0.19; E2=0.38 E1 Strain E2 Stress - Strain diagram of a metal alloy OA.T= 18.52 Mpa O B.T= 92.62 Mpa O C.T= 37.05 Mpa O D.T= 60.21 Mpa Stress (Mpa) 3
Q.1 The yield stresses (oy) have been measured using steel and aluminum specimens of various grain sizes, as follows: Material D (µm) σΥ (MPa) Steel 60.5 160 136 128 Aluminum 11.1 235 100 223 (a) Determine the coefficients o and kỵ in the Hall- Petch for these two materials. (b) Determine the yield stress in each material for a grain size of d=26 um.
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Show the typical Stress versus Strain curve for the following materials, and define the materials properties "The stress-strain curve can be used to read off the structural load ability of materials. For many materials, including metals, their loading bearing capability is one of the most important material properties". by reference to the diagram: Cavie d) Box is made from polypropylene
The state of stresses in the x and y directions at a point in a given material is shown in the figure below. If the value of the shear stress in the x-y axes Ty is 17N/mm2, find the maximum shear stress that can be found at this point in any possible direction. Round off your answer to the nearest N/mm2. 10 N/mm2 Txy 20 N/mm2 20 N/mm2 Txy 10 N/mm2
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