摘要
采用挤压铸造工艺制备了7A09铝合金,研究了挤压力及时效工艺对7A09铝合金组织和性能的影响。结果表明:以挤压力为25、50和75 MPa的挤压铸造工艺制备的7A09铝合金铸件内无气孔、缩孔等缺陷,其显微组织比采用普通铸造工艺制备的铝合金铸件致密;挤压铸造的合金晶粒和沉淀相比普通铸造的合金的细小,随着挤压力的增大,合金的硬度和抗拉强度升高,磨损质量损失减小;经120℃时效130 min后,挤压铸造的合金的磨损质量损失比普通铸造的合金显著减小,这是由于挤压铸造合金凝固时间缩短、沉淀相密度提高、晶粒较细小和共晶组织分布较均匀从而耐磨性显著改善所致。
7A09 aluminum alloy was prepared by extrusion casting technology,and the effects of extrusion force and aging process on the microstructure and properties of 7A09 aluminum alloy were studied.The results showed that(a)there were no defects such as porosity and shrinkage in the 7A09 aluminum alloy castings fabricated by extrusion casting with extrusion forces of 25,50,and 75 MPa,and its microstructure was denser than that of the aluminum alloy castings fabricated by common casting;(b)the grains and precipitates of the alloy fabricated by extrusion casting were smaller than those of the alloy fabricated by common casting,with the increase of extrusion force,the hardness and tensile strength of the alloy increased,and the wear mass loss decreased;(c)after aging at 120℃for 130 min,the wear mass loss of the extrusion cast alloy was significantly reduced compared to the commonly cast alloy,which was due to the fact that the extrusion cast alloy decreased in solidification time,exhibited a higher density of precipitates,smaller grains and more uniform distribution of eutectic structures,therefore its wear resistance was significantly improved.
作者
丁春艳
DING Chunyan(School of Physical Education and Nursing,Chengdu University of Arts and Sciences,Chengdu Sichuan 610499,China)
出处
《上海金属》
CAS
2024年第2期16-21,共6页
Shanghai Metals
