The cost of replacing components which become worn or damaged during service has led to the development of a wide range of techniques known as “hardfacing”, which can restore the parts to a reusable condition. Many such repairs have a longer life than the original component because it is possible to deposit coatings more resistant to wear, impact, abrasion or corrosion than the original material. As a result, hardfacing is now widely used on many production components.

Hardfacing deposits are usually fairly thick (2mm and upwards) and for some applications intermediate sub-layers must be used to inhibit metallurgical problems with the final deposit. Electrodes and filler wires are available to give varying degrees of wear, corrosion, or heat resistance and can be applied to small discrete areas such as valves and valve seats, or large areas such as shaft bearing surfaces or complete steel mill rolls. Hard facing is particularly associated with the earth moving equipment, cement ovens and rock crushing and processing industries.