metal treatment info Chemical Man

What is heat treatment in metal?

Heat treatment involves the use of heating or chilling, normally to extreme temperatures, to achieve a desired result such as hardening or softening of a material. Heat treatment techniques include annealing, case hardening, precipitation strengthening, tempering, normalizing and quenching.

What is surface treatment of metals..

Surface treatment of metal is a process in which parts or components made out of metal or plastic are treated before any actual coating takes place. ... The surface layer forming on a metal that is scheduled for chemical coating is created due to a chemical reaction that's non-electrolytic in nature.

How do you quench steel

Heat the entire piece of steel slowly at first. Then, concentrate the heat on the area that is to be hardened, such as a chisel point or screwdriver blade tip, until that area glows red hot. Quench the steel in a fluid. Dipping the hot steel into a liquid or gas rapidly cools it, hardening the metal.

Why do you quench steel in oil

When hardness can be sacrificed, mineral oils are often used. These oil based fluids often oxidize and form a sludge during quenching, which consequently lowers the efficiency of the process. The quenching velocity (cooling rate) of oil is much less than water.

How do you heat treat metal?

Once hardened, the part must be tempered. Tempering is the reheating of the part to a temperature well below the hardening temperature to reduce the hardness and increase the toughness. This may range from 350°F to as high as 1350°F depending on the steel and the hardness desired.

What is the surface treatment?

Surface treatments typically are removing material, adding material or chemically altering the surface. Surface treatments are widely used in most industries to provide improved surface properties of a component.

What is used to harden steel?

The term hardened steel is often used for a medium or high carbon steel that has been given heat treatment and then quenching followed by tempering. The quenching results in the formation of metastable martensite, the fraction of which is reduced to the desired amount during tempering.