摘要
通过拉伸试验、晶间腐蚀与应力腐蚀实验,结合金相观察和高分辨透射电镜分析,研究微量Ti和Cr对Al-Zn-Mg-Cu-Zr合金弥散相、再结晶与性能的影响。结果表明:在Al-Zn-Mg-Cu-Zr合金中,添加0.04%Ti(质量分数,下同)可使合金抑制再结晶的能力降低,从而导致合金的力学性能和抗应力腐蚀性能降低;复合添加0.04%Ti和0.04%Cr,形成含有少量Cr的Al3(Zr,Ti)弥散相,合金抑制再结晶的能力显著增强,合金在保持高强度的同时,抗应力腐蚀性能显著提高,抗拉强度为687.6 MPa,屈服强度为651.4 MPa,比不含Ti和Cr的合金分别提高15.3 MPa和7.8 MPa,应力腐蚀裂纹萌生时间由161 h延长至306 h。
The effects of minor Ti and Cr additions on dispersion precipitate, recrystallization, microstructure and properties of Al-Zn-Mg-Cu-Zr aluminum alloy were investigated by tensile test, intergranular corrosion and stress corrosion cracking test, optical microscopy and aberration corrected high resolution transmission electron microscopy. The results show that compared with the Al-Zn-Mg-Cu-Zr alloy, the addition of minor Ti to Al-Zn-Mg-Cu-Zr aluminum alloy can decrease the ability of inhibit recrystallization during solid solution treatment, and then decrease the mechanical properties and the stress corrosion cracking resistance; The composite with minor Ti and Cr elements can form Al3（Zr,Ti） dispersion precipitates containing minor Cr, and can significantly enhance the ability of inhibit recrystallization, which significantly enhances the stress corrosion cracking resistance while maintaining high strengths. The σb is 687.6 MPa and σ0.2 is 651.4 MPa, improving 15.3 MPa and 7.8 MPa respectively higher than those alloys without Ti and Cr elements, and the time for the stress corrosion cracking initiation improves from 161 h to 306 h.
出处
《粉末冶金材料科学与工程》
EI
北大核心
2016年第1期50-58,共9页
Materials Science and Engineering of Powder Metallurgy
基金
国家重点基础研究发展规划资助项目(2012CB619502
2010CB731701)
国家重大科研仪器设备研制专项(51327902)
湖南省自然科学基金资助项目(12JJ6040)
国家自然科学基金资助项目(51201186)
高性能复杂制造国家重点实验室开放课题(HPCM-2014-03)
