10 Deformation Process

Question 1

1.The stresses and strains in metal forming are of which type, elastic or plastic?

Answer 1

The stresses and strains in metal forming of plastic deformation.

Question 2

2. What are some of the advantages of cold working relative to warm and hot working?

Answer 2

Advantages of cold working

1 No required heating of work

2 Better finish

3 As a specimen deforms, the grain flow causes desirable directional properties in the material

4 Produce more accuracies and with closer tolerances

5 Increases in strength and hardness occur through strain hardening

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While, during hot working, temperatures above the recrystallization cause deformation.

Question 3

3. How does increasing temperature affect the deformation processes?

Answer 3

Increasing temperature results in the 1 REDUCTION OF STRENGTH and 2 (REDUCTION OF) STRAIN HARDENING in a material.

Question 4

4. Will the strain rate’s effect on flow stress more sensitive at low temperature or high temperature?

Answer 4

The strain rate’s effect on flow stress is more sensitive at HIGH TEMPERATURES.

While at room temperature, the strain rate is practically negligible.

However, as temperature increases, the strain rate of a material becomes increasingly important in determining flow stress.

Question 5

5. Name the four basic bulk deformation processes.

Answer 5

1 Rolling

2 Forging

3 Extrusion

4 Wire/bar drawing

RFEW

Question 6

6. What are the advantages of thread rolling over thread cutting (machining).

Answer 6

Advantages of thread rolling over thread cutting include;

1 Higher production rates

2 Better material utilization

3 Stronger threads

4 Better fatigue resistance

HBSB

Question 7

7. Identify the three major categories of sheet metalworking operations

Answer 7

1 Bending operations

2 Deep/cup drawing

3 Shearing processes

BDS

Question 8

8. What is springback in sheet-metal bending? Why will it happen?

Answer 8

Describes the increase in included angle of the bent part relative to included angle of forming tool after the tool is removed.

Springback occurs because the bending pressure is removed. During this occurrence, the elastic energy remains in the bent part, causing it to recover partially toward its original shape.

Question 9

9. I-Beam is commonly used in structure. Typically, how was it manufactured?

Answer 9

I-Beams are manufactured through shape rolling, in which a square cross-section is formed into a shape such as an I-Beam.

Question 10

10. The picture below is an Aluminum colling fin for computer’s CPU. How was it manufactured?

Answer 10

The aluminum fin for the pictured computer CPU was manufactured through the Bulk Deformation’s Extrusion Process.