3.1.1 Methods for Investigating And Testing Materials

Question 1

What is material testing ?

Answer 1

Material testing is used to help select the most appropriate material for a product application.

Question 2

How do you ensure a test is robust ?

Answer 2

• Use the same size material for each test
• ensure environmental conditions are the same
• use the same testing equiptment
• use one person to take all measurments
• ensure they van all be measure the same way

Question 3

What is a simple work shop test ?

Answer 3

using basic tools and equiptment.

Question 4

What is a simple test method to test tensile strength ?

Answer 4

less deflection under load means material has more tensile strength.

Question 5

What is a simple test method to test toughness ?

Answer 5

they absorb impact

Question 6

What is a simple test method to test hardness ?

Answer 6

The material is tested using a dot punch, and force from a hammer. the smaller the indent the harder the material.

Question 7

What is a simple test method to test thermal conductivity ?

Answer 7

using a bunsen burner under one end of materials of test piece
recording time it takes for temperature to reach a set point.

Question 8

What is a simple test method to test electrical conductivity ?

Answer 8

using multimeter

Question 9

What is a industrial test ?

Answer 9

Usually carried out in labs with testing machinery.

Question 10

Indutrial test for Tensile strength ?

Answer 10

tensometer machine - using test piece that is clamped and stretched
One clamp moves on worm drive
puts the material under tension.
Gives info on elastic limit yield point , graph is plotted

Question 11

Indutrial test for toughness ?

Answer 11

Izod impact test - notched test piece - a pendulum is released from a fixed position
Energy absorbe3d by test piece.

Question 12

Indutrial test for hardness ?

Answer 12

Rockwell , Brinell Vicker pyarmid testing - using indentation

Question 13

what is the rockwell hardness test ?
(Hardness Test)

Answer 13

diamond indenter - hard material that will mot deform

Question 14

What is the Brinell Test?
(Hardness Test)

Answer 14

A hardened standard sized ball is forced into the material surface using a pre load.

Question 15

what is the vickers pyramid hardness test ?

Answer 15

Used for very hard materials
using a square based pyramid to indent surafce of a material - miscroscope is used to measure size of indent.

Question 16

What is non destructive testing ?

Answer 16

testing carried out on products rather than materials samples , the product is not desroyed during the testing, used to find defect in a material.
Xray
Ultrasonic

Question 17

What are the two types of non destructive testing.

Answer 17

Ultrasonic - sound waves being pulsed - different sounds indicate faults.
X-ray - beam passed through material material - image is projected on screen so small details can be seen.

Question 18

How to test for malleability and ductility.

Answer 18

When the test piece is bent 90 degrees, crack on outside suggest lack of ductillity and cracks on inside suggest lack of malleabilty.