Material Testing Flashcards
What is annealing?
To soften the metal, improve machinability, relieve internal stresses, and increase ductility
What is normalising?
To refine the grain structure, improve toughness, and relieve internal stresses
What is hardening?
To increase the hardness and strength of the metal
What is quenching?
To lock in the hardened structure of the metal by rapid cooling
What is tempering?
To reduce brittleness and improve toughness in hardened metals.
What is case hardening?
To create a hard outer surface while maintaining a softer, tough core
What is the process of case hardening?
Heat the surface of the metal and introduce carbon or nitrogen
Quench it to harden the outer layer
What is the process of tempering?
Reheat the hardened metal to a temperature below its critical point
Cool it in air
What is the process of quenching?
Heat the metal to a specific temperature
Quench it in a medium like water, oil, air, or polymers
What is the process of hardening?
Heat the metal to a high temperature (austenitizing temperature for steel)
Quench it rapidly in a cooling medium (water, oil, or air)
What is the process of normalising?
Heat the metal above its critical temperature
Cool it in still air at room temperature
What is the process of annealing?
Heat the metal to a specific temperature
Hold it at that temperature for a certain period.
Cool it slowly (usually in a furnace)
