Preparation And Characterization Ti₃AlC₂/Al Composites

2belongs to ternary layered ceramic materials M(n+1)AXn, including M is the element of the transition metals, A is ⅢA or ⅣA group elements, X is C or N, n=1,2,3. Ti3AlC2has hexagonal structure, space point group P63/mmc. Ti3AlC2has a unique combination of the excellent properties of both metals and ceramics. It has a low hardness, low density, good electrical conductivity, good thermal shock resistance, etc. So far, Production of T13AIC2in many ways, such as the spark plasma sintering (SPS), hot isocratic pressing (HIP), hot-pressing (HP) and mechanical alloying (MA).In this study, Ti, Al and C elemental powders were used as raw materials and mechanical alloying process of containing T13AIC2powder, and the heat treatment process to purify the mixed powders after mechanical alloying for preparation of T13AlC2provides a new way to obtain high purity Ti3AIC2. Through the systematic study of mechanical alloying parameters, the ratio of raw materials and the doped Si on the synthesis of Ti3AlC2optimize the mechanical alloying to prepare Ti3AlC2the optimal parameters; Computer simulation of the MA process, MA process and the principle. SPS sintering the powder of high purity Ti3AlC2and Al mixed powder in order to preparation Ti3AlC2/Al composites and characterization microstructure and properties.D/Max2500PC X-ray diffraction and jade was used to analyze the phase composition of the powders and lattice constant; JSM-5600LV scanning electron microscopy was used to study the microscopic structure and morphology characteristics of samples. Its density was measured by Archimedes’. UNMT test system was used for the wear of composite friction performance measurement; the hardness of the sintered sample was determined using HXD-1000micro hardness.The results show that elemental powders (Ti, Al, and C) were successfully prepared by mechanical alloying Ti3AIC2powder and Ti3AlC2content of92.2wt%. Doped with a small amount of Si, Ti3AlC2content of95.1wt%. MA the powders by the SPS high temperature purification, the product Ti3AlC2purity of more than99wt%; Ti3AlC2composites was prepared by SPS, and the relative density of composites increased with increasing sintering temperature. When the sintering temperature reaches550℃, the relative density of the composite material has reached97%; When the sintering temperature reaches550℃, the relative density of the composite material has reached97%; In the sintering temperature of550℃, the hardness of the composites is about the180HV; When the sintering temperature of500℃, when the Ti3AlC2add content5vol%, then the coefficient of friction of composite is only16%of the pure Al, Ti3AlC2add content5vol%when the sintering temperature of500℃, the friction coefficient of composite materials optimum value of approximately0.1869.