The Experimental Research Of Al₂O₃-TiN-CaF₂ Self-lubricating Ceramic Cutting Tool

Al₂O₃-Ti N-CaF₂ self-lubricating ceramic cutting tool material is fabricated by hot-pressuring technology to solve the problem that the cutting liquid application results in wasting of resources and pollution,and involves the matrix material of Al₂O₃,reinforcement phase of Ti N,the solid lubricant of CaF₂ and the sintering additive of Mg O,Ni,and Mo.The as-prepared self-lubricating ceramic cutting tool is used to perform the cutting experiment.The research contents are as follows:1.Al₂O₃-Ti N-CaF₂ self-lubricating ceramic cutting tool material is fabricated,which undergoes processes including ball milling,drying,cold pressure forming and vacuum sintering,and involves the matrix material of Al₂O₃,reinforcement phase of Ti N,the solid lubricant of CaF₂ and the sintering additive of Mg O,Ni,and Mo.the flexural strength,hardness and fracture toughness are 615 MPa,11.8GPa and3.6MPa·m^1/2.the existence of CaF₂ is invalidated by XRD test for Al₂O₃-Ti N-CaF₂ self-lubricating ceramic cutting tool material2.Al₂O₃-Ti N-CaF₂ self-lubricating ceramic cutting tool material is used to conduct the cutting performance test with single variable method,and obtains the optimized cutting parameters.The cutting force,cutting temperature,flank wear of Al₂O₃-Ti N-CaF₂ self-lubricating ceramic cutting tool material were studied by means of dynamometer,infrared thermal imager,and optical microscope.SEM and spectrophotometer are used to observe the wear morphology of rake and flank surface.The results show that the wear form is abrasive wear when cutting 45 steel.3.Compared the cutting force,cutting temperature and the calculated friction coefficient of Al₂O₃-Ti N ceramic cutting tool and Al₂O₃-Ti N-CaF₂ self-lubricating ceramic cutting tool material,Al₂O₃-Ti N-CaF₂ self-lubricating ceramic cutting tool material has lower friction coefficient and lubricant effort.The optimized lubricant effort is obtain when cutting speed is 109¹20m/min,feed speed is 0.102mm/r and back cutting depth is 0.4mm.4.The cutting performance test for Cr12 mold steel is carried out by Al₂O₃-Ti N-CaF₂ self-lubricating ceramic cutting tool,the flank wear and the work piece surface quality is obtained with different cutting speed.the performance curve is compared between machining Cr12 mold steel and 45 steel,and the results show that Al₂O₃-Ti N-CaF₂ self-lubricating ceramic cutting tool has more suitable to machine the 45 steel,which can acquire good cutting life and surface roughness.5.The cutting experiment is performed with the incorporation Minimum Quantity Lubrication?MQL?and self-lubricating ceramic cutting tool.The results show that the lower cutting temperature is obtained by the combination of MQL and self-lubricating ceramic cutting tool,and the friction coefficient keeps invariant due to that MQL system reduces the cutting temperature which angst the forming lubricating film,and thus the friction coefficient increases.