STUDY OF WEAR-RESISTANCE OF SOME INDIGENOUS HARD-FACING ALLOYS.

Hard facing is the process of welding a layer, edge or point of metal on to a part to increase its resistance to abrasion, erosion, where systematic lubrication against abrasion is impossible, as on an oil-well drilling tool, agricultural and earth moving equipment, mining tools, engine valves, chemical processing equipment, etc. Hard-facing also extends the life of lubricated parts such as metal working dies and areas of machine parts that have a high rate of wear. Hard-faced surfaces are usually more resistant to wear, heat and corrosion than case-hardened or flame-hardened surfaces. Also critical local areas of large components can be hard-faced where it would be impractical or impossible to harden components by heat-treatment. The present work is concerned with the study of hardness and wear resistance of several indigenous hard facing alloys in different situations. Three different alloys were tested for wear resistance having been used as pins under load braking a grinding disk which is similar to conventional sand stone cutting test.