Manufacturing Processes

1. 1. Residual Stress in materials can NOT be caused by:

• Mechanical Deformation

• Welding, casting, or quenching

• Phase Changes

• Uniform heating and cooling

2. 2. ………… is a measure how much strain a material can undergo before fracture.

• Plasticity

• Toughness

• Ductility

• Malleability

3. 3. What type of idealized stress–strain curve is presented in the figure below?

• elastic, perfectly plastic

• elastic, linearly strain hardening

• rigid, perfectly plastic

• rigid, linearly strain hardening

4. 4. The element representing the maximum in-plane shear stress with the associated average normal stresses is oriented ……. from the element representing the principal stresses.

• 0°

• 45°

• 90°

• 180°

5. 5. Which one of the following statements is wrong?

• In upsetting a workpiece is compressed between two flat dies.

• In the forging process, the sample is considered as very wide if (w >> a).

• The work done to deform a material is a product of the stress and strain.

• Flow stress is defined as the instantaneous value of stress required to continue plastically deforming a material.

7. 6. Which one of the following statements is wrong?

• Small-diameter rolls and/or small reductions in thickness tend to work the metal plastically at its surfaces.

• Alligatoring occurs in the nose and tail of the slab due to inhomogeneity of the material.

• In the rolling process, as friction increases, the neutral point shifts toward the exit.

• In the rolling process, a higher reduction percentage shifts the neutral point toward entry.

8. 7. Systematic error …..

• occurs due to chance

• occurs in every single measurement

• measurements of the same thing will vary in unpredictable ways

• occurs only when data is recorded or written down incorrectly

9. 8. Which one of the following statement is correct regarding the figure below:

• High precision, low accuracy

• High precision, high accuracy

• Low precision, high accuracy

• Low precision, low accuracy

10. 9. We should be able to capture …….. of all measurements (X-values) within the Control Limit range.

• 68.2%

• 99.73%

• 100%

• 95.45%

11. 10. Which one of the following statements is wrong regarding the weld heat affected zone (HAZ):

• Material in this region is heated, but remains below melting temp.

• Retains chemical composition of base metal, but microstructures (and properties) are altered.

• Material in this region has smaller microstructures compared to the base metal.

• Effects are usually negative, and is often the location of weld failures.