【摘要】 通过预球磨和低温球磨原位制备了尺寸约300nm的TiCp与铝的复合颗粒,采用搅拌铸造法将复合颗粒与镁合金复合,制备了TiCp/AZ91复合材料,并研究了材料的微观组织和性能。结果表明,通过低温球磨可以原位生成TiCp/Al复合颗粒,搅拌能够将复合颗粒搅入镁合金中。TiCp体积分数低时(3%),制备的复合材料中TiCp分布比较均匀;体积分数较高时,TiCp沿晶界分布倾向增大;当体积分数达到7%时,TiCp主要沿晶界分布。性能测试结果表明,复合材料的室温抗拉强度达287.72MPa,弹性模量达69.23GPa。200℃下抗拉强度达245.49MPa,弹性模量达到51.32GPa。复合材料的蠕变性能为:170℃和55MPa以及175℃和60MPa下100h总蠕变量分别为0.182%和0.191%。细小的增强颗粒对位错和晶粒边界的钉轧作用是导致复合材料具有良好的高温拉伸和蠕变性能的原因。更多还原

【Abstract】 By pre-milling and cryogenic ball milling the TiCp /Al composite particles with size about 300 nm were prepared. By stirring casting technology, and compounding the composite particles and magnesium alloy, the TiCp /AZ91 composite was prepared, and its microstructure and mechanical properties were studied. Results indicate that by cryogenic ball milling the TiCp /Al composite particles can be in-situ produced, and the composite particles can be stirred into the magnesium alloy by stir. When the volume fraction was low (3vol.%), TiCp was well-distributed in the prepared composite. When the volume fraction was high, the distribution of TiCp tended to increase along the grain boundary, and if the volume fraction reached 7vol.% , TiCp mainly distributed along the grain boundary. The results of properties testing show that the tensile strength of the composite at room temperature reached 287 MPa, elastic modulus reached 69.23GPa. At 200℃, the tensile strength reached 245 MPa, elastic modulus reached 51.32 GPa. The total creeps of the composite at 170 ℃ with 55 MPa and at 175 ℃ with 60 MPa for 100 h were 0.182% and 0.191% , respectively. The nail rolling function of fine particles acting on dislocations and grain boundaries leaded to the composite having well high temperature tensile and creep properties.更多还原