Fabrication And Properties Of Ti₃AlC₂/Fe Composite

With the rapid development of metal mineral, energy, transportation, equipment manufacturing and environmental industries, the request of general properties to Fe-matrix is getting higher and higher. Due to have the special properties of both metal and ceramics, MAX compound has became the hotspot of research inland and overseas as the wild phase. This work mainly studies the fabrication and heat-treatment properties of Ti3AlC2/Fe composite.The missions of this work are:(1) To fabricate high purity of Ti3AlC2 powders and (10-30vol.%) Ti3AlC2 and Fe composite bulks. (2) Observed and studied structure and properties of Ti3AlC2/Fe composite materials under different sintering process. (3) Has explored the influence of Ti3AlC2/Fe's structure and properties by different sintern process. (4) Has discussed the high temperature mechanism of Ti3AlC2/Fe composit bulks.The results show that high purity of Ti3AlC2 powders can be obtained by pressureless sintering the proper mole ratios of Ti;Al, Sn, Cpowders at 1450℃for 10 minutes. Take Ti3AlC2 and Fe powder as raw material, the compact Ti3AlC2/Fe composite can be obtained by pressureless sintering and hot pressure sintering at 1100℃～1400℃, and heat preservation of 30min-120min.In Ti3AlC2 of TiC and Al's inter-atomic forces is weaker van der Waals keys, under high temperature due to the existence of Fe, easy to decompose, the formation of TiC and Al. In Ti3AlC2/Fe composite sintering process, the formation of Al gradually decompose into Fe, at last in the formation of trace amounts of Fe (Al) alloy, and Fe will gradually into the TiC particles. The original shape of the TiC grains are gathered gradually separated by Fe and matrix uniformly distributed in Fe, the final Fe enhanced by nano-TiC metal ceramic composites.In pressureless sintering, the experiments on the range of sintering process can be prepared nanosized TiC/Fe composites can be got under the range of srintering process. Due to the presserless sintering, material preparation of sintered density is poorer, which has greatly affected the physical properties and electrical properties.Hot press sintering of Ti3AlC2/Fe compared the properties of composites by pressureless sintering have been greatly improved. For example, the flexural strength of 20Ti3AlC2/Fe increased from 190.16MPa to 1425.98MPa, density increased from 6.028g/cm3 to 7.134g/cm3. This is because sintering is substantially reduced porosity of composite materials, and to the reaction Fe and Ti3AlC2 are more fully. So the performances of Ti3AlC2/Fe composite materials have greatly improved.This article innovation spot lies in use micron level Ti3AlC2 and Fe powder, using the home position responded a production nanometer level strengthens Ti3AlC2/Fe compound materials. The innovation of this work is a production nanometer level strengthens Ti3AlC2/Fe compound materials are sintered which use micron level Ti3AlC2 and Fe powder as raw material by the home position respondse.