5wt% n-SiC对7075铝合金微观组织与力学性能的影响

Effect of 5wt% n-SiC on Microstructure and Mechanical Properties of 7075 Aluminum Alloy

采用高能球磨与热压烧结相结合的方法制备了5wt%n-Si C/7075铝基复合材料,研究了5wt%n-Si C对7075铝合金组织与性能的影响。结果表明:高能球磨后,5wt%n-Si C/7075铝基复合粉体较7075合金粉体明显细化。当转速350 r/min,球料比20:1,球磨时间20 h时,n-Si C均匀分布到7075合金颗粒中。由于n-Si C的均匀分布对7075铝合金产生细晶强化与弥散强化的作用,使得热压烧结温度为620℃,加压100 MPa,保温保压1h制备的5wt%n-Si C/7075铝基复合材料的致密度、硬度及抗压强度均优于相同工艺制备的7075铝合金,尤其抗压强度较7075铝合金提高约58.4%。

5wWo n-SiC particle reinforced 7075 A1 matrix composite was prepared by high energy ball milling and hot pressing sintvring method. The effects of 5wt% n-SiC on the microstructure and mechanical properties of 7075 aluminum alloy were studied. The results show that 5wt% n-SiC/7075 aluminum matrix composite powder is significantly refined compared with 7075 alloy powder after high energy ball milling. With the milling speed of 350 r/rain, the ball to powder ratio of 20：1 and the ball milling time of 20 h, the n-SiC uniformly distributes in 7075 alloy particles. Because the uniform distribution of n-SiC makes the fine grain strengthening and dispersion strengthening of 7075 aluminum alloy, the density, hardness and compressive strength of 5wt% n-SiC/7075 aluminum matrix composite prepared by hot pressing at 620℃ with an applied pressure of 100 MPa for lh increase obviously compared with 7075 aluminum alloy prepared by the same process, especially, the compressive strength increases by about 58.4% compared with 7075 aluminum alloy.