Consider the tensile stress-strain diagrams in Figure 8 - 20 labeled 1 and 2 and answer the following questions. These curves are typical of metals. Consider each part as a separate question that has no relationship to previous parts of the question.

Figure 8 - 20 Stress - strain curves (for Problem 8 - 1)
(a) Which material h as the larger1 work hardening exponent? How do you know?
(b) Samples 1 and 2 are identical except that they were tested at different strain rates. Which sample was tested at the higher strain rate? How do you know?
(c) Assume that the two stress-strain curves represent successive tests of the same sample. The sample was loaded, then unloaded before necking began, an d then the sample was reloaded. Which sample represents the first test: 1 or 2? How do you know?

Transcribed Image Text:

2 CD Strain