A load versus displacement diagram is show n in Figure 6-29 for a metallic glass. A metallic glass is a non-crystalline (amorphous) metal. The sample was tested in compression. Therefore, even through the load and displacement values are plotted as positive, the sample length w as shortened during t he test. The sample had a length in the direction of loading of 6 mm and a cross-sectionalarea of 4 mm2. Numerical values for the load an d displacement are give n at the points marked with a circle and an X. The first data point is (0, 0). Sample failure is indicated with an X. Answer the following questions.
(a) Calculate the elastic modulus.
(b) How does the elastic modulus compare to the modulus of steel?
(c) Calculate the engineering stress at the proportional limit.
(d) Consider your answer to part (c) to be the yield strength of the material. Is this a high yield stress or a low yield stress? Support you r answer with an order of magnitude comparison for a typical polycrystalline metal.
(e) Calculate the true strain at the proportional limit. Remember that the length of the sample is decreasing in compression.
(f) Calculate the total true strain at failure.
(g) Calculate the work of fracture for this metallic glass based on engineering stress and strain.

Figure 6-29 load versus displacement for a metallic glass tested in compression for Problem 6 - 40

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8000 7000 6000 5000 (0.100, 7020) X (0.105, 7020) 2 3 4000 3000 2000 1000 0 0.00 0.02 0.04 0.06 0.08 0.10 0.12 0,14 Displacement (mm)