【摘要】 采用氮气雾化法制备Zr质量分数为0.25%的7056铝合金粉末,然后通过放电等离子烧结技术制备超高强7056铝合金,研究烧结温度对合金致密性、微观组织和力学性能的影响。结果表明:气雾化法制备的7056铝合金粉末组织为枝晶结构,平均粒度为43.4μm,晶粒尺寸为1～2μm,晶界处存在明显的溶质元素偏聚。放电等离子烧结的7056铝合金接近全致密。随烧结温度升高,合金的压缩屈服强度先增大后减小,在烧结温度为480℃时,强度最高,为284.7 MPa。经过固溶时效处理后,合金强度显著提高,烧结温度为420℃的合金,时效后强度达到575.9 MPa。时效态合金的强度随烧结温度升高而降低。更多还原

【Abstract】 The bulk ultra-high strength 7056 aluminum alloys were prepared by spark plasma sintering(SPS) combined with nitrogen atomization process. The effects of sintering temperatures on the density, microstructure and mechanical properties of this consolidated alloy were studied. The results showed that the gas-atomized 7056 aluminum alloy particles of an average of 43.4 μm exhibited a cellular-like dendritic structure with a grain size of about 1-2 μm, obvious solute element segregation was found at grain boundaries. The nearly full dense bulk body could be obtained by spark plasma sintering. It was the yield strength maxium of 284.7 MPa of the consolidated alloy during compression when the sintering temperature was 480 ℃. With the increase of sintering temperature, the yield strength during compression first increased and then decreased. The mechanical properties of the consolidated alloy could be obviously enhanced after solution and aging treatment, the yield strength of alloy was amaxium of 575.9 MPa as sintering temperature was 420 ℃,and gradually decreased with the increase of sintering temperature.更多还原