B Durga Prasad

Hardfacing is the process of depositing a layer or layers of metal of specific properties on certain areas of metal parts that are exposed to wear by one of the various welding techniques. Hardfacing offers more than other wear prevention treatments. It is part of a well-established practice and in the majority of cases, existing equipment can be used. Hardfacing provides protection in depth by depositing a layer or layers of metal. Hence it can be applied in a required thickness to give required protection. A wide variety of deposit types are available which are designed to withstand different forms of wear and service conditions. Hardfacing is applied only to specific areas of metal parts that are exposed to wear. Hence it can be applied selectively and in different thicknesses to suit the exact requirements of a workpiece. This is the most economical way of fighting wear. Hardfacing is a particular form of surfacing that excludes the application of materials primarily for corrosion prevention or resistance to high temperature scaling or the application of low hardness, friction over-lays to prevent galling.