(C) Global Journal Of Engineering Science And Researches [30-33] GLOBAL JOURNAL OF ENGINEERING SCIENCE AND RESEARCHES SOME STUDIES OF HARDFACING AND METALLURGICAL PROPERTIES OF MILD STEEL USING SHIELDED METAL ARC WELDING PROCESSES

Many engineering materials can be characterized by set of properties and these are varied. Heat treatment is a controlled heating, cooling of metals for the purpose of altering their properties and can perform their function without a concurrent change in the product shape. Both physical and chemical properties can altered by heat treatment such as case hardening. This method is particularly useful for improving resistance to the surface indentation fatigue and wear. Some of the applications of these case hardening are gear teeth, milling cutters, cams, shafts, bearings, cutting tools and dies.through hardening of these parts would not be desirable. The hard part must be the necessary toughness, impact resistance, corrosive wear and for this application, some surface crack can propagate rapidly through the part and cause the total failure. Hardfacing is the deposition of different metal over the parent metal to achieve required properties. Alloys can be added by various ways to hardfacing surface by various means,such as incorporating in the powdered form in flux and making electrodes of alloying elements. The alloying elements can be selected according to purpose such as chromium, vanadium, tungsten etc carbide alloys offer excellent abrasion resistance and good heat resistance