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Engineering Material
Test 2 Short Answer
Question | Answer |
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Complete the phrase: Because macroscopic plastic deformation corresponds to the motion of large numbers of dislocations, | the ability of a material to plastically deform depends upon the capability of it dislocations to move |
Name the 4 strengthening mechanisms for metals: | Cold Working Grain Size Reduction Precipitation-Hardening Solid-Solution Strengthening |
Explain why materials that behave in a ductile fashion at room temperature may behave in a brittle fashion at colder temperatures. | The ductile brittle transition temperature (DBBT) is the minimum temperature in which a given material has the ability to absorb a specific amount of energy without fracturing. As temperatures decrease, a material's ability to deform in a ductile matter. |
Explain why brittle fracture is undesirable (syntax in answer is mehh but the answer was right...) | Because It happens without warning, and spectacularly, without warning, sometimes explosively or destructively so. |
Explain the stages of elastic and plastic deformation during a simple tensile test. Refer to the figure below. (has important labels) | Important labels to remember: Tensile Strength line Axes Labels (sigma, epsilon) Local-Global vertical line Elastic, Plastic Necking Load is applied, microvoids form, then coalesce, necking begins, shearing at edge, Fracture |