The Preparation Of Particle Reinforced Aluminum Matrix Composites

Aluminum matrix composites have high strength, high specific modulus, good thermalconductivity, good secondary processing, and are widely used in aerospace, building materials,automotive, high-speed trains and other fields, as the choice of lightweight materials. But thetraditional process of preparing composite materials is easy to produce pores, inclusions.Between the matrix and reinforcement the wettability is bad and interface combination is notsolid,affecting the mechanical properties of the material. Reasonable preparation of aluminumcomposite material can disperse the fine enhance phase.The interface has a good combinationand wettability with the substrate.In this paper, expanded research on the preparation process of particle reinforcedaluminum composite material, The main contents: The mixture powders of Al and Zr werehigh-energy ball-milled and studied the influence of the milling process parameters (millingtime, ball feed ratio and speed) on the microstructure of the composite powder; The process ofaluminum matrix composite were studied by stir casting with TiO2powder and the effects ofstirring time and stirring rate on the microstructure and properties of the material wereanalysed; Study the thermal stability of Al3Ti particle reinforced aluminum matrix compositesunder high temperature.The microstructure and mechanical properties of the material were characterized withoptical microscopy, SEM, XRD, hardness tester, universal tensile machine obtained the mainresults are as follows:(1)With the increasing of planetary ball mill energy,the diffraction peak of Al-Zrcompounds powder gradually broadened and the intensity decreased. Grain refinement occurseven amorphous structure. (2)TiO2powder was,used to prepare aluminum matrix composites containing Ti,withextension of mixing time can increase the hardness and stability of the material; stirring faster,higher hardness values.(3)Study the thermal stability ofAl3Ti particle reinforced aluminum matrix compositesunder high temperature.When the temperature is less than200℃, the hardness tends to bestable;When the temperature exceed200℃, the hardness increases significantlyas thetemperature decreased.No significant effect was happened on the grain size and hardnessvalue of material with the exposure time.Its temperature fracture characteristics based ductilefracture, coexist ductile and brittle fracture.Dimples of tensile fracture were coarse andshallow.The initiation of more cleavage plane in fracture was found.