Ferrous Materials and Non-Ferrous Metals and Alloys 1 introduction

(1) Low Temperature Tempering:

 The work is heated between 150 and 250°C for a

specific time. The objective of this procedure is to relieve internal stresses and to

increase the ductility with much reduction in hardness. Low temperature tempering

is applied in the heat treatment of carbon and low alloy steel cutting tools as well

measuring instrument and components that have been carburised and surface

hardened.

(2) Medium Temperature Tempering:

 The work is heated between 350 and 450°C for a

specific time before being allowed to cool off in air or quenched in certain media.

The martensite is converted into secondary troostite. The results provide reduction

in hardness and strength of metal and improvement in ductility. The process is utilized

in production of laminated springs and coils to ensure toughness.