COMPARISON OF VARIOUS MECHANICAL PROPERTIES OF FSPed AND BARE AISI 4337 STEEL

Friction Stir Processing (FSP) of AISI 4337 steel was done with Tungsten carbide (wc) tool under two different rotational speeds 100rpm and 200rpm, with feed rate of 30 mm/min and plunge depth of 1 mm. Optical microscopy analysis was conducted and the grain size in the processed zone was found to be refined to 2 µm, and 3 µm respectively, in comparison to base steel (average grain size 50 µm). The grain size was found to be increasing with increase in revolving speeds. This may be increasinge due to the temperature parameter to increase in strain rate while the recrystallization. The mechanical properties like micro hardness, tensile and bending were studied. After annealing process, the carbide particles was observed in original marten site phase. According to the increase in grain size. Good strength-ductility observed with YS of 650 Mpa and 970 Mpa. This is may be fact that increase in the grain boundaries decreases in the grain size. Friction stir processing also modified the properties of AISI 4337 steel microstrurcture. KEYWORDS: Friction Stir Processing, Microstructure, Mechanical Properties, Grain Refinement