摘要进入高速列车时代以来，铁路客运量的需求日益增加，列车速度性能的要求也不断提高，高强度铝合金材料在高速列车车体上得到了广泛的应用。然而铝合金材料在潮湿气体中具有抗应力腐蚀开裂（SCC）敏感性，所以有必要对其抗SCC性能进行研究。25290
本文通过对高速列车用6N01铝合金的应力腐蚀性能的研究，结合实验室条件，进行了自加载悬臂梁试验以及三点加载应力腐蚀试验，测量6N01铝合金应力腐蚀强度因子和裂纹扩展速率，研究应力腐蚀过程及机理，比较5、6、7mm不同厚度的铝合金板材的抗应力腐蚀性能以及T4、T5态的铝合金板材应力腐蚀敏感性的差异。
经试验研究发现，在实验条件下 6N01铝合金板材会发生应力腐蚀现象，在三点加载作用下受拉应力作用的表面氧化膜首先被破坏，并在表面产生点蚀和晶间腐蚀，随着晶粒慢慢剥蚀表面产生了腐蚀坑，腐蚀坑之间逐渐连成片并出现裂纹。测量计算得到6N01铝合金临界应力强度因子为4.9-5.6Mpa左右，裂纹扩展速率约为4.5*10-3mm/h。在一定厚度范围内，5mm的铝合金板材腐蚀速率较慢，腐蚀程度较低，其抗应力腐蚀敏感性较6mm和7mm板材更低。T4状态的铝合金板材比T5状态的的应力腐蚀敏感性更低。
关键词 6N01铝合金 应力腐蚀 KISCC 三点加载 裂纹扩展速率
毕业论文设计说明书外文摘要
Title Study of Stress Corrosion Cracking of High-strength aluminum alloy
Abstract
Enter into the high-speed train era, the demand of railway passenger traffic
have increased quickly，the need of passenger train speed performance improved too,So the high-strength aluminum alloy in high-speed train body has been widely used.However,there are SCC susceptibility of aluminum alloy material in the wet gas, so it is necessary to study its resistance to SCC.
This topic through 6N01 aluminum alloy used for high-speed trains to inquiry stress corrosion, Combined with laboratory conditions,Carried out the self-loading izod test and three point loading stress corrosion test.Measured the intensity factor and stress corrosion crack growth rate of 6N01 aluminum,researched the stress corrosion mechanism,compared the different thicknesses of aluminum alloy sheet 5,6,7mm resistance to stress corrosion and T4, T5 state aluminum plate stress corrosion sensitivity of difference.
Experimental research has found that 6N01 aluminum alloy is sensitive to stress corrosion,surface oxide film under tensile stress in three-point loading effects are first destroyed and pitting and corrosion on the surface of the grain.With the grain slowly eroded surface corrosion pits, the gradual emergence of microcracks between corrosion pits.6N01 aluminum measure calculated critical stress intensity factor of about 5Mpa, the crack growth rate is about 4.5E-3.Within a certain range of thickness aluminum sheet thinner the better resistance to stress corrosion, stress corrosion resistance of aluminum alloy sheet can be better than 5mm and 7mm of 6mm. Aluminum alloy sheet T5 T4 state than the state more resistant to corrosion.
Keywords 6N01 aluminum Stress corrosion KISCC Three loaded Crack growth rate
目 次
1 引言 1
1.1 高速列车的车体材料 1
1.2 铝合金概论 2
1.2.1 变形铝合金的分类 2 高强度铝合金板材的应力腐蚀性能研究:http://www.751com.cn/cailiao/lunwen_18987.html