Improvement of Mechanical Properties of Alloy Steel Type (40x) by Using Heat Treatments

Heat treatment is a process or several processes contained heating and cooling a solid metal or alloy is such way as to obtain desired conditions or properties, or recovery the properties was existed in metal or alloy which exposed to certain operational proces. The objective of this study is to investigate effect of heat treatment on mechanical properties of low-chromium alloying steel (1.1%Cr) with (0.4%) carbon and these properties are: tensile strength, hardness, elongation, and reduction in area. The heat treatments included full annealing which consist of heating steel to (870oC) and cooling in furnace, hardening which done by heating to (870oC) and quenching in oil, and tempering in (300oC and 600oC ). The mechanical properties was measured before and after heat treatment as illustrated in the diagrams between heat treatment mechanical properties. The important of this research is that it used a material was used only in militarism fields and calculated its properties to compared them with another steels types for using in civil fields.