Influence of the microstructure on the cyclic stress-strain behaviour and fatigue life in hypo-eutectic Al-Si-Mg cast alloys
Influence of the microstructure on the cyclic stress-strain behaviour and fatigue life in hypo-eutectic Al-Si-Mg cast alloys
复制标题
显微组织对亚共晶 Al-Si-Mg 铸造合金循环应力应变行为和疲劳寿命的影响
DOI：
10.1051/matecconf/201816515004
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发表时间：
2018
期刊：
影响因子：
--
通讯作者：
Walther
中科院分区：
文献类型：
--
作者：
Tenkamp;Knorre;Michels;Walther
铝合金是汽车和航空航天工业中具有能源和成本效益的部件的有前途的候选者，因为与钛合金相比，铝合金具有优异的强度重量比和相对较低的成本。由于现代铸造工艺和后处理（例如热等静压）导致缺陷的频率和尺寸降低，最薄弱的环节取决于显微组织特征，例如二次枝晶臂间距（SDAS）、Si共晶形态和α-Al固溶体硬度。据此，疲劳调查的微观结构特征的循环应力-应变行为的影响，以及在低周和高周疲劳制度的疲劳机制进行。为此，研究了具有不同Si共晶形貌和α-Al固溶体硬度的铸造铝合金EN AC-AlSi 7 Mg 0.3试样。为了比较单调和循环应力-应变曲线，准静态拉伸试验和增量阶跃试验进行了两种组织条件。结果表明，与单调加载相比，循环加载导致材料的硬化。基于损伤参量Woehler曲线，可以用一次幂定律预测亚共晶Al-Si-Mg铸造合金在单调和循环载荷下的损伤进程和疲劳寿命。
Aluminium alloys are promising candidates for energy-and cost-efficient components in automotive and aerospace industries, due to their excellent strength-to-weight ratio and relatively low cost compared to titanium alloys. As modern cast processing and post-processing, e.g. hot isostatic pressing, result in decreased frequency and size of defects, the weakest link depends on microstructural characteristics, e.g. secondary dendrite arm spacing (SDAS), Si eutectic morphology and α-Al solid solution hardness. Hereby, fatigue investigations of the effect of the microstructure characteristics on the cyclic stress-strain behaviour as well as fatigue mechanisms in the low cycle and high cycle fatigue regime are performed. For this purpose, samples of the aluminium cast alloy EN AC-AlSi7Mg0.3 with different Si eutectic morphology and α-Al solid solution hardness were investigated. To compare the monotonic and cyclic stress-strain curves, quasistatic tensile tests and incremental step tests were performed on two microstructure conditions. The results show that the cyclic loading leads to a hardening of the material compared to monotonic loading. Based on damage parameter Woehler curves, it is possible to predict the damage progression and fatigue life for monotonic and cyclic loading in hypo-eutectic Al-Si-Mg cast alloys by one power law.
DOI：
10.1007/bf02735006
发表时间：
2006-12-01
影响因子：
3
作者：
Campbell, John
通讯作者：
Campbell, John