Thermal Processes in Metalworking

Annealing involves slow cooling from elevated temperatures, while quenching involves very fast cooling using a cooling medium like water or oil.

Quenching is done to retain the phases of elevated temperatures at room temperature.

Induction hardening involves passing an alternating current of high frequency through an induction coil enclosing the steel part to be heat treated.

<p>Flame hardening is used for large work pieces and complicated cross-sections where induction heating is not easy to apply.</p> Signup and view all the answers

<p>Precise control over the area to be hardened, ability to harden reentrant surfaces, very high speed of hardening and no separate quenching step.</p> Signup and view all the answers

<p>The hardening is shallower than in induction and flame hardening.</p> Signup and view all the answers

<p>Surface layers of low carbon steel are enriched with carbon up to 0.8-1.0% by diffusing carbon at an elevated temperature.</p> Signup and view all the answers

<p>Cyaniding is done in a liquid bath of NaCN at lower temperatures and shorter times compared to carburizing.</p> Signup and view all the answers

<p>Low carbon steels are strengthened by cold work.</p> Signup and view all the answers

<p>Ferrite and pearlite.</p> Signup and view all the answers

<p>Medium carbon steels can be heat treated by austenitizing, quenching, and tempering.</p> Signup and view all the answers

<p>High carbon steels are used for tool applications such as knives, razors, and hacksaw blades.</p> Signup and view all the answers