Preparation And Design Of2014Al Matrix Composites Reinforced With Nano-sized TiCp And SiCp

There is increasing attention to nano-sized particle reinforced aluminum matrixcomposites because of its excellent mechanical properties. However, some problems aboutpreparing the nano-particles reinforced aluminum matrix composites are urgent to be solvedsuch as the distribution of nano-sized reinforced particles. Composites can reduce cluster ofnano-sized particles and gain excellent properties by proper addition of nano-sized particles.So it is very important to optimize the proper addition. Moever, people design particlereinforced aluminum matrix in the view of biomimetics, excepting for excellent properties ofcomposites.In this study, nano-sized TiCp reinforced2014Al composites were prepared by powdermetallurgy and hot extrusion. The effect of nano-sized TiCp content on microstructure andtensile properties was studied. Meanwhile, two kinds of aluminum matrix laminatedcomposites were prepared by hot rolling. The tensile properties and preparation process oflaminated composites were also studied. The results are mainly concluded as below:(1) The TiCp/2014Al composites prepared by powder metallurgy showed densemicrostructure and presenced low porosity, nano-sized TiCp mainly distributed at the grainboundary；With the addition of TiCp increasing from0vol.%to5vol.%, the cluster of TiCpgot worse and the porosity got higher; After hot extrusion, the TiCp/2014Al compositesshowed more denser and lower porosity, Nano-sized TiCp distributed along the direction ofextrusion and became more uniform, With the addition of TiCp increasing from0vol.%to5vol.%, the enrich area of TiCp increased.(2) With the addition of TiCp increasing from0vol.%to5vol.%, the ambient tensilestrength of TiCp/2014Al composites increased first and then decreased, whereas the elongation decreased all the time; It is revealed that3vol.%nano-sized TiCp/2014Alcomposites possessed the best tensile properties, of which the yield strength(320MPa) andultimate tensile strength(509MPa)are30MPa and54MPa higher than those of2014Al, butelongation (18.0%)was1.5%lower than that of2014Al.(3) Powder metallurgy and hot rolling were successfully used to prepare three-layeredlaminted composites; with the addition of nano-sized SiCp, tensile strength of three-layeredlaminted composites increased at both ambient and high temperature; At ambienttemperature, yield strength(287MPa) and ultimate tensile strength(470MPa) of Model Cthree-layered composites were30MPa and55MPa higher than2014Al, but elongation(18.6%) was1.7%lower than2014Al; At200℃,three-layered composites of Model Eexhibited the most optimum properties for yield strength(271MPa) and ultimate tensilestrength(326MPa) were34MPa and21MPa higher than those of2014Al, but elongation(16.9%)was4.9%lower than2014Al.(4) TiCp/1060Al laminated composites were successfully prepared by hot rolling andsintering, with the increase of rolling reduction, the yield strength and ultimate tensilestrength of laminated composites improves slightly; with addition of Cu powder and highersintering temperature and pressure, yield strength and ultimate tensile strength of laminatedcomposites improved more. When sintering temperature was525℃, TiCp/1060Al laminatedcomposites exhibited the most optimum properties for yield strength(134MPa) and ultimatetensile strength(158MPa) were21MPa and17MPa higher than those of1060Al laminatedmaterial, but elongation (10.7%)was1.5%lower than1060Al.