Based In Situ Study The Microstructure And Properties Of Aluminum Matrix Composites Synthesized TiC-7075

This paper mainly use the in situ synthesis technology to made TiC-7075aluminummatrix composites, based on the thermodynamic analysis of Al-Ti-C, judge the feasibilityof the composite material preparation, discusses different process parameters effect on the TiC-7075aluminum matrix composites and mechanical properties. Microstructure researchmainly observe the grain size, phase composition and distribution of TiC in compositematerials by optical microscope, scanning electron microscopy and transmission electronmicroscopy; Mechanical properties mainly research the different process parameters (particleconcentration,particle size and melting temperature) the influence on the hardness and impacttoughness on TiC-7075aluminum matric composites. The results show that:1. The thermodynamic analysis shows that the reaction gibbs free energy of is less thanzero of Al-Ti-C system in the temperature range from973K to1773K. That note in thistemperature range the reaction can occur and can self sustain. Ceramic powder TiC reactionmechanism is: external heat source to generate A13Ti between Ti and Al, followed by theexothermic reaction TiC formed between Ti and C,A13and C reaction.2. We can determined by experiment that There only have TiC particles in the compositeswhen mTiC:mC=2.9:1in preform. According to the microstructure observation and analysis,TiC plays the role of nucleation and prevent grain growth in composite materials.3. Different process parameters is determined by orthogonal experimental design method(particle concentration, particle size and melting temperature of TiC-7075aluminumcomposite material hardness and impact toughness, the results show that the shadow: ringcompound material hardness factor mainly is the particle size, followed by the particle content,and influence the impact properties of composite materials mainly melting temperature. Thecomprehensive index measuring and analysis its best combination is A1B2C3, namely particlecontent is3.6%, particle size is400mesh, melting temperature at1050℃of thecomprehensive performance of the best, the hardness value is107HB, impact toughness valueof15.1J/cm2. The original7075aluminum alloy as-cast organization hardness increased by40.79%, impact toughness is increased by47.02%.