Applications and Processing of Ceramics

Applications and
Processing of Ceramics

Callister Chapter 13




Lecture 3 Electron micrograph
of a glass-ceramic
Instructor Dr. Amir Khesro


02/04/2019 Dr Amir Khesro AWKUM
Chapter 13 - 1

, Chapter 13: Applications and
Processing of Ceramics

ISSUES TO ADDRESS...
• How do we classify ceramics?

• What are some applications of ceramics?

• How is processing of ceramics different than for metals?




02/04/2019 Dr Amir Khesro AWKUM
Chapter 13 - 2

, Classification of Ceramics

Ceramic Materials

Glasses Clay Refractories Abrasives Cements Advanced
products ceramics
-optical -whiteware -bricks for -sandpaper -composites -engine
-composite -structural high T -cutting -structural rotors
reinforce (furnaces) -polishing valves
-containers/ Adapted from Fig. 13.1 and discussion in
bearings
household Section 13.2-8, Callister & Rethwisch 8e. -sensors




02/04/2019 Dr Amir Khesro AWKUM
Chapter 13 - 3

, Glass-ceramics
v A glass-ceramic is formed by the heat treatment of glass which
results in crystallisation
v The product is a fine grained polycrystalline material
v The formation of these small glass-ceramic grains is, in a sense, a
phase transformation, which involves nucleation and growth
stages
v only specific glass compositions are suitable precursors for glass-
ceramics due to the fact that some glasses are too stable and
difficult to crystallise whereas others result in undesirable
microstructures by crystallising too readily in an uncontrollable
manner
v A glass-ceramic is usually not fully crystalline; with the
microstructure being 50-95 volume % crystalline with the
remainder being residual glass.
02/04/2019 Dr Amir Khesro AWKUM
Chapter 13 - 4