Categories
- MIM (175)
Purpose-to increase strength & hardness of a green compact
Carried out at a temperature below the highest melting constituent.
Furnaces may be either the electric resistance,gasfired or oil fired type.
Principal variables-temperature(generally within 70-90% of the melting point of metal or alloy),time(10min.-8 hours)&furnace atmosphere.
Sintering process is concerned with
-diffusion(surface of particles as temperature rises)
-densification(decreases porosity,increase particle contact area)
-recrystallization&grain growth(between particles at the contact area)
Decrease in free energy due to decrease of surface area.