Investigations On Tool Wear And Machined Surface Propenies Based On Minimum Surface Wear Rate

High efficiency and high quality manufacturing technology is an advanced general technology. It is widely used in the aviation, aerospace, auto, mould etc which have made significant effects to improve the level of the manufacturing technology. In the modern industry, the trend of the worldwide manufacturing industry are quality assurance, efficiency improvement, cost reduction, energy saving and emission reduction among of which high efficiency is much more important. This paper based on the minimum surface wear rate theory studied the cutting parameters optimization, tool wear mechanisms and machined surface layer properties of iron-based superalloy GH2132which provided theoretical and technical guidance to practical production.Under various cutting conditions, the surface wear rate of turning iron-based superalloy GH2132was studied. There is always a speed range exiting where the tool goes into the stable wear stage. In this range, the surface wear rate firstly decreases then increases followed with the improvement of the cutting speed, and reaches the minimum value at a certain cutting speed.In a certain cutting speed range, the surface wear rate reaches minimum value at the optimal cutting speed. The cutting temperature which the minimum surface wear rate corresponds to results in minimum the micro-hardness of workpiece surface layer. The surface micro-hardness specific value of tool-workpiece interface, elongation and ultimate strength all reach the minimum value. In the process, all factors mentioned above minimize the radial wear of tool and the surface wear rate.Cutting parameters of turning iron-based superalloy GH2132based on the minimum surface wear rate were optimized. With the optimal cutting speed, the tool gets the strongest tool wear, the least tool consumption, the longest dimension tool life and the specific dimension tool life. Processing precision is improved as well.Three-dimensional cutting force theoretical model was presented. Under the optimized cutting parameters, cutting force of turning iron-based superalloy GH2132 is studied. The resultant force tends to decline with the improving of cutting speed. It is lower and more stable when the optimal cutting speed is with vo=90m/min (the workpiece material without heat treatment) and with vo=70m/min (the workpiece material after heat treatment). The minimum surface wear rate and the corresponding cutting temperature varies between370～400℃.Tool wear mechanism of turning Iron-based superalloy GH2132was studied. The workpiece material before heat treatment, the wear type of rake face is the carter; the main wear mechanisms are adhesion and oxidation wear. The workpiece material after heat treatment, the carter is not found on the rake; the main wear mechanisms are adhesion and diffusion wear.The machined surface layer properties of turning iron-bases superalloy GH2132were studied. It is found that the minimum surface roughness value is achieved at the optimal speed or around. Micro-hardness, hardness depth and work-hardening capacity of iron-bases superalloy GH2132(after heat treatment) were researched. The experiment proved that when the optimal cutting speed is vo=70m/min, the surface micro-hardness, the hardness depth, work-hardening capacity reach the minimum value.