Investigation the friction drilling of A7075-T651 aluminium alloy and ST37 steel materials experimentally.

Investigation the Friction Drilling of A7075-T651 Aluminium Alloy and St37 SteelMaterials Experimentally.Friction drilling is a process that utilizes heat effect between conical tool and thework material to form a hole. The purpose of friction drilling method is increased thefixtures length utilizes of bushing height such as screw threads for thin work pieces. Thetool used in this study has 8 mm, 10 mm, and 12 mm diameters, 8 mm, 16 mm, and 24 mmcylindrical shape lengths, 900 tip point angle, 240, 360, 480 conical angles and the toolmaterials were HSS and WC. The spindle speeds used 2400 rpm, 3600 rpm, 4800 rpm, andthe feed rates 50 mm/min, 75 mm/min, and 100 mm/min respectively. 2mm, 4mm, and6mm thickness ageing tempered A7075 ? T651 material that widely uses in aerospace andautomotive industries and St37 materials used for experiments in this friction drillingstudy. In this study the effects of selected experimental parameters on the surfaceroughness, bushing height and out diameter, bushing and flake shapes, fixture strength,micro hardness and micro structure were investigated. Friction drilling and non-traditionalhole making methods were compared. The photographs of the micro structure were takenwith SEM microscopy and the changes in micro structure were investigated. At the resultof this study investigated that for 2mm material thicknesses smaller than 8mm diameters,360, for 2mm and 4mm thicknesses hl=8mm, and for 6mm material thickness hl=16mmwere the most appropriate parameters and with increasing material thickness the bushingshape were formed more optimum. According to the surface roughness criteria,50mm/min, 4800rpm and 360 tool conical angle were the most appropriate parameters infriction drilling of A7075-T651. According to all criteria 2400rpm for 50/min, 3600rpm for75mm/min and 4800rpm for 100mm/min parameters were the most appropriate parametersin friction drilling of St37 alloy. In friction drilling of A7075-T651 the maximum microhardness were got 70?m away from the hole surface and in friction drilling of St37 themicro hardness were not changed so much as aluminium alloy.Keywords: Friction Drilling, Surface Roughness, Micro Hardness Bushing Height