Experimental Research Of Al₂O₃-TiC Micro-textured Ceramic Tools By In-situ Molding Process

There are many researches on micro-texture ceramic cutting tools.The main purpose is to realize the anti-wear and anti-wear effect of ceramic cutting tools in the cutting process.But most of the processing for the micro-texture tools are used to prepare the tools first,and then use the laser processing and other methods to process micro-texture in the surface of the tools.Filled solid lubricant up the micro-texture manually when it needed.The preparation cycle is long.In this paper,the method of in-situ molding is used to process the micro-texture ceramic cutting tools.Make the high-purity graphite into micro-texture punch,and ceramic powder can be prepared at the same time.The punch and the powder sintered at the same time into the sleeve after cold pressing.The micro-texture is placed into the ceramic material,then through late processing to prepare the required micro-texture ceramic tools by in-situ molding process.The research is as follows:（1）On the basis of reading a large number of related literatures,TiC with different mass fraction was sintered at different sintering temperatures to prepare Al₂O₃-TiC ceramic samples.Tested their mechanical properties,the material composition was determined to be 25%of the Ti C mass fraction,the sintering temperature was1600℃.The obtained hardness,fracture toughness and flexural strength were 16.97GPa,7.31 MPa·m^1/2 and 489.7 MPa,respectively.（2）The Al₂O₃-TiC ceramic samples with different morphological micro-texture were obtained by hot pressing and sintering.and their mechanical properties were tested.Compared with the non-textured Al₂O₃-TiC ceramic samples,when the texture spacing is increased from 0 to 200μm,the mechanical properties are gradually increased and reached the maximum at 200μm.The hardness,fracture toughness and flexural strength of the composites are 17.14GPa,7.41MPa·m^1/2 and 512MPa.When the micro-texture spacing continues to increase,the mechanical properties of the value of a downward trend.（3）The friction and wear tests of Al₂O₃-TiC ceramic specimens with different micro-texture morphology were carried out to study the changes of micro-texture width and pitch with speed and load and the material wear.The results showed that when the load was 30N and the rotation speed was 100r/min,the micro-texture Al₂O₃-TiC ceramic samples with different spacing were more likely to obtain lower friction coefficient,and the friction coefficient was the lowest when the micro-texture spacing was 0.2mm,it is0.37.The wear pattern of the non-woven texture was mainly adhesive wear,and the micro-texture Al₂O₃-TiC ceramic specimen was mainly adhesive wear and abrasive wear.When the load was 110N and the rotation speed was80r/min,the micro-texture Al₂O₃-TiC ceramic specimen with variable width was more likely to obtain the lower friction coefficient,and the friction coefficient was 0.4457when the micro-texture width was 0.15mm.The wear pattern of the non-woven texture was mainly adhesive wear,and themicro-texture Al₂O₃-TiC ceramic specimen was mainly abrasive wear and brittle fracture.（4）Five kinds of different morphological micro-texture Al₂O₃-TiC ceramic tools were designed and fabricated.The cutting test was carried out to study the cutting force,cutting temperature,friction coefficient of the rake face,surface roughness,chip morphology and wear surface of the rake face.The results showed that the cutting force and cutting temperature of the micro-texture Al₂O₃-TiC ceramic tools were generally lower than that of the non-woven tool.The lowest friction coefficient of the front face was the micro-texture Al₂O₃-TiC ceramic tools,which micro-texture spacing,width and height are 0.1mm,the average value was 0.339,and the lowest surface roughness was the the micro-texture Al₂O₃-Ti C ceramic tools,which micro-texture spacing are0.15mm,width and height are 0.1mm,the average value was 0.704;cutting speed was low when the chip was curved and spiral,cutting speed was high when the chip was flocculent and chip-like.The Al₂O₃-TiC ceramic tool was mainly bonded and abrasive,and the micro-texture Al₂O₃-TiC ceramic tools were mainly wear and tear.Groove wide micro-texture Al₂O₃-TiC ceramic tools wear area were larger.The above results showed that the micro-texture Al₂O₃-TiC ceramic tools could improve the mechanical properties of Al₂O₃-TiC ceramic tools to a certain extent,and it was helpful to reduce the friction coefficient,cutting force and cutting temperature.