CAJ | 학술논문

一批次7075铝合金航空座椅产品经熔铸、挤压、机械加工、热处理及阳极氧化处理后表面局部出现黑色条纹。对该批次航空座椅产品进行外观检查，化学成分、金相组织、硬度、扫描电镜及能谱等分析。结果表明：7075合金铸棒均匀化处理不充分，大块第二相沿着挤压方向呈条带状分布，在后续热处理中难溶于铝基体；航空座椅产品所采用的挤压板材挤压比选择偏小，挤压机吨位选择不当，导致基体中存在铸态组织，大块第二相未能充分破碎。
일비차7075려합금항공좌의산품경용주、제압、궤계가공、열처리급양겁양화처리후표면국부출현흑색조문。대해비차항공좌의산품진행외관검사，화학성분、금상조직、경도、소묘전경급능보등분석。결과표명：7075합금주봉균균화처리불충분，대괴제이상연착제압방향정조대상분포，재후속열처리중난용우려기체；항공좌의산품소채용적제압판재제압비선택편소，제압궤둔위선택불당，도치기체중존재주태조직，대괴제이상미능충분파쇄。
Local black stripes were found on the surface of aero seat products of 7075 aluminum alloy after anodic-oxidation treatment. Macro and micro observation, chemical composition analysis, metallographic structure analysis, hardness testing, and energy spectrum analysis were carried out to find out the cause. The results show that the homogenization treatment of 7075 alloy rods was not sufficient, and massive second phase distributed like bonds along the direction of extrusion, which was difficult to dissolve in the Al matrix in the subsequent heat-treatment. Besides, the smaller extrusion ratio of the extruded sheet and the improper tonnage selection of extrusion press caused the existence of cast structure in the matrix and the massive second phase being not fully broken.