2. Test 1 rev

Review Question Lecture 8: Glass and Ceramic

1. Disc brake as shown in Figure 1 can be produced by using metal powder or ceramics

processing. Compare the differences and similarities in producing the disc brakes by using the mentioned processes.

(8 marks)

Figure 1: Disc Brake 2. Propose structure sequences in producing the ceramic disc in a large volume. Use

sketches to elaborate in detail the propose sequence. (8 marks)

3. One of the process in producing the ceramic part is drying. The defect found is distort

or warp. Explain why ceramic parts may distort or warp during drying and propose would be done to avoid this defect?

(5 marks) 4. One of the phenomenon in ceramic component particularly in a long term service life

is static fatigue. Discuss how static fatigue affect the disc brake service life. (5 marks)

5. Compare any variances from the design considerations for ceramics disc brakes from those made from other materials.

(5 marks)

Review Question Lecture 9: Composite Processing 1. One of the product that can be produced using composite material is a bicycle frame as

shown in Figure 1. Whisker generally been used as the reinforcing material for the frame. Discuss the significant gains in using whiskers as a reinforcing material?

(6 marks)

Figure 1: Composite bicycle frame

2. Identify and discuss the processes that are capable of producing parts with the following fiber orientations:

(a) uniaxial (b) cross-ply (c) in-plane random (d) three-dimensional random

(8 marks)

3. Compare and discuss from the perspective of product design and volume in adopting the manual tape laying and machine the tape laying machine in producing composite product.

(6 marks)

4. Honeycomb structures are structures that have the geometry of a honeycomb to allow the minimization of the amount of used material to reach minimal weight and minimal material cost refer figure 2. . Suggest and justify how a consumer product can utilized the honeycomb structures in making a better product from various perspective.

(8 marks)

Figure 2: Honeycomb structure

5. Most of sports equipment such as bicycles, tennis racquets, golf club and baseball bats are generally made from composite material. Discuss and give justification of using composites for these particular equipment and application.

(8 marks)

Review Question Lecture 10: Polymer Processing

1. Figure 1 shows a plastic part that been made using an injection moulding process. The main components of the injection moulding process would be the mound and screw extruder. You are one of the process engineer that in designing the plastic part, you have been assigned to clarify some matters arising in manufacturing the plastic part. The following are the questions that been raised.

Figure 1: Plastic injection moulding part

a. One of the issues concern is difficulties in understanding of the process

especially the screw extruder, therefore you are assigned to describe the function of the screw extruder to the designer. Your description should be aid with a sketches.

(8 marks)

b. A question been raised is how does the injection moulding is capable of

producing parts with complex shapes and fine detail. Discuss.

(4 marks)

c. As it is now the plastic part is produce using thermoplastic. Distinguish

whether the part can be produce using thermosetting plastics, if possible what changes that need to be made on the processing method. (5 marks)

d. A small pores is identified as one of the defect occurring on the plastic injection molded part. The solutions identified is to dry the material before injection. Justify how does drying can solved the defect.

(5 marks)

e. In producing high volume plastic parts, cycle time is one of the crucial factors that need to consider in the injection moulding process. List and distinguish the factors that will have an effect on the injection moulding cycle time.

(5 marks)

2. In injection-molding operations, runner as shown in Figure 2 is shredded , The runner then transform into a recycle pallets to be used in the injection moulding process. Discuss the issues that may be arising in using recycled pellets for manufacturing products compare to virgin pellets.

(6 marks)

Figure 2: Runner form plastic injection moulding part

3. Discuss with the aid of sketches a film bag making process. Justify why this process are perform vertically.

(8 marks)

4. Cycle time is one of the crucial factors that need to consider in the thermoforming process. List and distinguish the factors that will have an effect on the thermoforming cycle time.

(5 marks)

5. Cycle time is one of the crucial factors that need to consider in the t compression molding process. List and distinguish the factors that will have an effect on the compression molding cycle time.

(5 marks)

Review Question Lecture 11: Surface Finish and Surface Technology

1. Compare and discuss on the surface roughness of various products shown in the Figure 1. Justify why the component exhibit the surface roughness that you indicate.

(8 marks)

(a) Aluminum foils (b) Stainless-steel pots and pans (c) Ball-bearings (d) Plastic housings for socket

Figure 1: Example of various products

2. In designing parts or components for engineering application the requirement of surface-roughness would vary in relating to their application. Interpret why the variation occurring and discuss with one specific parts or components as an example.

(6 marks)

3. In certain processes such as machining the high surface roughness is desirable and on the other hand it is not acceptable that can cause friction. Justify with an example of machining that higher surface roughness (high friction) and lower surface roughness (no friction) is desirable and acceptable.

(6 marks)

4. Propose applicable steps to follow for reducing friction in a manufacturing process. (8 marks)

5. Discuss with examples the impact of wear on molds, tools, and dies and how it affects the manufacturing operation.

(6 marks)

6. One of the solution to reduce wear on molds, tools, and dies is to use lubricants. List and evaluate the optimal requirements of a lubricant before it is use to reduce the wear.

(6 marks)

7. Discuss the tribological differences between ordinary machine elements (such as gears, cams, and bearings) and metalworking processes using tools, molds, and dies. Consider such factors as load, speed, and temperature.

(8 marks)

8. Many parts in various appliances and automobiles have to be replaced because they were worn. Describe the methodology you would follow in determining the type(s) of wear these components have undergone.

(8 marks)