Ceramics

Question 1

What is a ceramic?

Answer 1

A combination of:

1. Non-metallic elements
2. Metallic and non-metallic elements

Question 2

What are the three forming methods for ceramics? And give two examples for each method

Answer 2

1. Pressing
   
   • Die pressing
   • Isostatic pressing
2. Casting
   
   • Slip casting
   • Tape casting
3. Plastic forming
   
   • Extrusion
   • Injection moulding

Question 3

Advantages and disadvantages of Die pressing

Answer 3

Advantages

Good dimensional control due to rigid die

Disadvantages:

Agglomeration of dry powder
Non-uniform transmission of applied pressure

Question 4

Advantages and disadvantages of isostatic pressing

Answer 4

Advantages:
Less powder movement
No die walls
Ability to press relatively complex shapes to a uniform density

Disadvantages:
Inferior dimensional control

Question 5

Advantages and disadvantages of Slurry casting

Answer 5

Advantages:
Uniform packing density
Can form large components and complex shapes

Disadvantages:
Narrow range of wall thickness
Variable wall thickness is difficult to cast
Shrinkage control is complex

Question 6

How are ceramics generally characterised?

Answer 6

By bend testing, also known as flexural testing.

It defines the maximum stress at failure. Which is known as the modulus of rupture (MOR)

Question 7

What is bioceramics? What are some applications?

Answer 7

Ceramics and glasses that are biocompatible with
human tissue and that are placed in the body to
replace a function.

Functions:
Hip replacements, Knee replacements, tendons, ligaments, dental implants, bone repair after tumour injury.