Heat Treatment of Metals

Process;

metal is heated then allowed to cool SLOWLY

Effect;

metal becomes softer, more ductile and less brittle

Process;

metal is heated and then cooled RAPIDLY by plunging into cold water or oil

Effect;

metal becomes harder but more brittle

Process (for steel);

cleaned and then gently heated, causing it to change colour

Effect;

the different colours show how tough the metal is becoming.