【摘要】 采用粉末冶金方法和等温锻造技术制备了15%Si Cp/Al-Cu-Mg复合材料锻件,通过光学显微镜(OM)、扫描电镜(SEM)、透射电镜(TEM)、能谱仪(EDS)、X射线衍射(XRD)和室温拉伸测试等方法研究了固溶温度与固溶时间对复合材料锻件微观组织和力学性能的影响。结果表明,热处理固溶温度较低、时间较短时,可溶性第二相粒子未充分回溶到铝基体中,铝基体的固溶强化效果不理想,材料强度较低;然而,固溶温度过高易导致材料过烧,从而导致材料的强度和塑性均降低。对复合材料物相分析表明,锻造态复合材料中的第二相主要是Al2Cu,Mg2Si以及少量的含Fe相,经510℃固溶2 h后,Al2Cu相可以充分回溶,而Mg2Si和含Fe相依然残留在基体中。复合材料最佳固溶温度是510℃,最佳固溶时间是2 h。此时获得的力学性能为:抗拉强度(Rm)=579 MPa、屈服强度(Rp0.2)=390 MPa、延伸率(A)=7%。更多还原

【Abstract】 15% Si Cp/ Al-Cu-Mg composite fabricated by powder metallurgy was processed by isothermal forging. The effects of solution treatment parameters on microstructure and tensile properties of the composite were studied by optical microscopy( OM),scanning electron microscopy( SEM),transmission electron microscope( TEM),energy dispersive spectrometer( EDS),X-ray diffraction( XRD) and tensile testing. The results showed that the insufficient solution time and lower solution temperature were not beneficial to the re-solution of soluble second phase particles into the matrix and the strength increase of the composite after natural aging. The composite was easily over-burned by high solution temperature,which reduced the strength and the plasticity. The results of XRD and EDS showed that the re-solved particles were Al2 Cu,but Mg2 Si and minor compounds containing Fe were always present during solution treatment. The best solution temperature and time of the composites were 510 ℃ and 2 h,respectively. And the tensile strength( Rm),yield strength( Rp0. 2) and elongation( A) of the composite were 579 MPa,390 MPa and 7%,respectively.更多还原