Extrusion: A Comprehensive Guide for Advanced Diploma in Engineering Students

Question 1

Which material property is most crucial for successful impact extrusion?

Accepted Answer

Ductility

Answer

Strength

Answer

Hardness

Answer

Toughness

Question 2

What is the primary function of a die cushion in extrusion?

Accepted Answer

To prevent product distortion and improve dimensional accuracy

Answer

To reduce extrusion pressure

Answer

To control the flow of material

Answer

To lubricate the tooling

Question 3

What is the primary purpose of using a mandrel in extrusion?

Accepted Answer

To shape the interior of the extrusion

Answer

To reduce the extrusion pressure

Answer

To improve the surface finish

Answer

To prevent product defects

Question 4

Which of the following is a primary advantage of direct extrusion over indirect extrusion?

Accepted Answer

Increased production rate

Answer

Higher extrusion force required

Answer

Reduced surface roughness of the extruded product

Answer

Improved dimensional accuracy

Question 5

In impact extrusion, the punch moves at what speed?

Accepted Answer

Very high

Answer

Very slow

Answer

Moderate

Answer

Variable

Question 6

What is the purpose of a mandrel in extrusion?

Accepted Answer

To form the inner surface of the extruded product

Answer

To reduce friction between the billet and the die

Answer

To control the flow of the extruded material

Answer

To increase the extrusion force

Question 7

Which type of extrusion is typically used for producing seamless tubes and pipes?

Accepted Answer

Hydrostatic extrusion

Answer

Direct extrusion

Answer

Indirect extrusion

Answer

Impact extrusion

Question 8

What is the primary drawback of hydrostatic extrusion?

Accepted Answer

High cost of equipment

Answer

Limited choice of materials

Answer

Complex process control

Answer

Low production rates

Question 9

Which of the following materials is NOT suitable for extrusion?

Accepted Answer

Glass

Answer

Aluminium

Answer

Steel

Answer

Copper

Question 10

What is the purpose of a die in extrusion?

Accepted Answer

To shape the extruded product

Answer

To reduce friction between the ram and the billet

Answer

To control the extrusion pressure

Answer

To increase the extrusion temperature

Question 11

Which of the following is NOT an application of extrusion?

Accepted Answer

Casting automotive parts

Answer

Producing window frames

Answer

Manufacturing electrical cables

Answer

Extruding dental implants

Question 12

Which extrusion method produces bars or wires with enhanced tensile strength along the extrusion direction?

Accepted Answer

Direct extrusion

Answer

Indirect extrusion

Answer

Impact extrusion

Question 13

What is the primary advantage of using impact extrusion?

Accepted Answer

Ability to produce complex shapes and high-strength components

Answer

High production rates and reduced tooling costs

Answer

Low material waste and improved surface finish

Question 14

Which factor has no significant impact on the extrusion force required in the process?

Accepted Answer

Die angle

Answer

Material yield strength

Answer

Extrusion ratio

Answer

Extrusion temperature

Question 15

What is the primary function of a mandrel in extrusion?

Accepted Answer

To shape and support the inner surface of hollow extrusions

Answer

To reduce friction between the billet and the container

Answer

To control the flow rate and temperature of the material

Question 16

Which of the following is NOT a controllable parameter in extrusion that can influence the properties of the extruded material?

Accepted Answer

Chemical composition of the billet

Answer

Extrusion temperature

Answer

Ram speed

Answer

Extrusion ratio

Question 17

What is the primary distinction between direct and indirect extrusion?

Accepted Answer

The direction of ram movement

Answer

The type of die utilized

Answer

The material being extruded

Answer

The extrusion temperature

Question 18

Which of the following materials is NOT appropriate for extrusion?

Accepted Answer

Ceramics

Answer

Aluminum

Answer

Steel

Answer

Polymers

Question 19

What is the major benefit of cold extrusion compared to hot extrusion?

Accepted Answer

Enhanced dimensional accuracy

Answer

Improved product strength

Answer

Reduced energy consumption

Answer

Improved corrosion resistance

Question 20

Which of the following is NOT a key advantage of direct extrusion?

Accepted Answer

Eliminated tooling costs

Answer

High production rates

Answer

Suitable for large cross-sectional areas

Answer

Excellent surface finish

Question 21

What is the primary purpose of the die in extrusion?

Accepted Answer

To shape the extruded material

Answer

To reduce friction between the material and the punch

Answer

To provide a seal to prevent material leakage

Answer

To cool the extruded material

Question 22

How do extrusion parameters, like temperature, speed, and pressure, influence the quality of the extruded product?

Accepted Answer

Extrusion parameters can affect product characteristics like strength, porosity, and surface finish.

Answer

Extrusion parameters have no significant impact on the extruded product's quality.

Answer

Higher temperature, slower speed, and higher pressure always result in a better-quality product.

Question 23

Which of the following is a primary advantage of direct extrusion compared to indirect extrusion?

Accepted Answer

Higher extrusion ratios and improved surface finish

Answer

Lower surface friction and reduced tooling costs

Answer

Increased material strength and enhanced corrosion resistance

Answer

Reduced extrusion speeds and simplified die design

Question 24

Which type of material is most suitable for impact extrusion in terms of its mechanical properties?

Accepted Answer

Ductile metals

Answer

Brittle ceramics

Answer

High-strength composites

Answer

Viscoelastic polymers

Question 25

What is the primary purpose of the mandrel in indirect extrusion?

Accepted Answer

To shape the internal cavity of the extruded product

Answer

To provide support for the billet during extrusion

Answer

To reduce friction between the billet and the extrusion chamber

Answer

To control the extrusion speed and maintain product quality

Question 26

What is the typical cross-sectional shape of the billet used in direct extrusion?

Accepted Answer

Round

Answer

Square

Answer

Rectangular

Answer

Triangular

Question 27

Which of the following is a practical application of impact extrusion?

Accepted Answer

Manufacturing toothpaste tubes

Answer

Producing seamless steel pipes

Answer

Extruding aluminum beverage cans

Answer

Shaping titanium components for aerospace applications

Question 28

Discuss novel and innovative applications of extrusion technology that extend beyond standard products.

Accepted Answer

Microfluidic devices for biomedical and analytical applications.

Accepted Answer

Composite materials with tailored properties for industries like aerospace and automotive.

Accepted Answer

Medical implants with complex geometries and biocompatible materials.

Answer

Standard pipes used in plumbing and construction.

Question 29

In the extrusion process, which factor does NOT significantly influence its outcome?

Accepted Answer

Tooling material

Answer

Temperature

Answer

Extrusion ratio

Answer

Die design

Question 30

Which type of extrusion is commonly used for producing seamless tubes and pipes?

Accepted Answer

Indirect Extrusion

Answer

Direct Extrusion

Answer

Impact Extrusion

Question 31

Which type of materials is most suited for impact extrusion processes?

Accepted Answer

Ductile materials

Answer

Non-metallic materials

Answer

Brittle materials

Answer

Hard materials

Question 32

What is the primary function of the ram in an extrusion process?

Accepted Answer

To apply pressure on the billet

Answer

To guide the billet through the die

Answer

To provide lubrication for the extrusion

Answer

To cool the extruded product

Question 33

What is the purpose of using a mandrel in indirect extrusion?

Accepted Answer

To create hollow profiles

Answer

To improve surface finish

Answer

To reduce friction

Answer

To increase extrusion ratio

Question 34

How is the extrusion ratio defined?

Accepted Answer

Ratio of the billet's cross-sectional area to the extruded product's cross-sectional area

Answer

Ratio of the product's length to the billet's length

Answer

Ratio of the extrusion pressure to the material's yield strength

Question 35

What is the primary objective of annealing as a post-extrusion heat treatment?

Accepted Answer

To soften the extruded product

Answer

To increase wear resistance

Answer

To improve corrosion resistance

Answer

To harden the extruded product

Question 36

Which material is NOT suitable for impact extrusion due to its high strength and hardness?

Accepted Answer

Steel

Answer

Aluminum

Answer

Copper

Answer

Brass

Question 37

What is the primary purpose of using a mandrel in the extrusion process?

Accepted Answer

To shape hollow sections

Answer

To reduce friction

Answer

To improve surface finish

Question 38

Which factor has the most significant influence on the extrusion pressure required?

Accepted Answer

Material properties

Answer

Die design

Answer

Extrusion speed

Answer

Billet temperature

Question 39

What is the main advantage of using the hydrostatic extrusion process?

Accepted Answer

Reduced friction and wear

Answer

Higher production rates

Answer

Enhanced surface finish

Answer

Lower tooling costs

Question 40

Which defect is commonly encountered in extruded products due to improper lubrication or high extrusion pressure?

Accepted Answer

Surface tears

Answer

Weld lines

Answer

Porosity

Answer

Cold shuts