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Hardening
McLeay Precision Engineering Ltd - Hardening

MPE Ltd have operated a cyanide salt furnace for through hardening and case hardening metal objects for more than thirty years. Finished results vary depending on metal type, furnace emersion time and various tempering options offered. Please call to discuss.

Carburising is a process where the steel is heated in a furnace. By means of a carbonaceous medium (salts) the outside layer of a carbon poor component is enriched with carbon by means of carbon diffusion. The increase of carbon content causes the material to harden. The result is a hard and wear resistant surface with a tough core. The temperature is relatively high since in austenite, the high temperature modification of iron, carbon is more soluble than in ferrite, the low temperature modification of iron.

The fully treated product has a hard surface (under compression) and a very tough inner part. Carburising causes the wear resistance of the surface to increase, the fatigue strength is improved as well as the toughness of the material. The strength and toughness increase are dependent on the steel alloy composition.