摘要
采用分子动力学方法研究β"-Mg_(5)Si_(6)析出相体积分数及深冷温度对Al-Mg-Si合金纳米力学特性的影响。模拟结果表明,与纯Al的峰值应力相比,当温度为77 K、β″析出相体积分数为0.107时,Al-Mg-Si合金的峰值应力提高97.05%。当β″析出相体积分数为0.107时,与300 K下样品的峰值应力相比,在27 K下该样品的峰值应力可提高23.55%。研究结果表明,深冷环境有助于提高总位错密度,使样品能够承受更大的应力,这为含β″相的Al-Mg-Si合金提供额外强度和韧性。降低温度可以明显抑制孔洞的萌生和生长(生长率27 K时下降88.5%),从而提高Al-Mg-Si合金的塑性。
The influences ofβ"phase volume fractions(PVF)and cryogenic temperatures on nanomechanical properties of Al−Mg−Si alloys were simulated by molecular dynamics.The simulation results show that when theβ"PVF is 0.107 at 77 K,the peak stress of Al−Mg−Si alloy is increased by 97.05%compared to that of pure aluminum.When theβ"PVF is 0.107,the peak stress of the sample at 27 K is increased by up to 23.55%compared to peak stress of sample at 300 K.Cryogenic environments help to enhance total dislocation density,allowing samples to withstand greater stress,which can provide additional strength and ductility.Temperature decrease can also appreciably inhibit the initiation and growth of voids(growth rate is decreased by 88.5%at 27 K),which contributes to the enhanced ductility.
作者
雷刚
高海涛
张昀
崔晓辉
喻海良
Gang LEI;Hai-tao GAO;Yun ZHANG;Xiao-hui CUI;Hai-liang YU(School of Mechanical and Electrical Engineering,Central South University,Changsha 410083,China;State Key Laboratory of Precision Manufacturing for Extreme Service Performance,Central South University,Changsha 410083,China;Light Alloy Research Institute,Central South University,Changsha 410083,China)
基金
supported by the High Performance Computing Center of Central South University,China,the High-tech Industry Technology Innovation Leading Plan of Hunan Province,China(No.2020GK2032)
the National Natural Science Foundation of China(No.52105419)
the Research Fund of the Key Laboratory of High Performance Complex Manufacturing at Central South University,China。
关键词
分子动力学
铝合金
β″相
强度
韧性
深冷温度
molecular dynamics
aluminum alloy
β″phase
strength
ductility
cryogenic temperature
