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投稿时间:2021-02-19 修订日期:2021-03-05
投稿时间:2021-02-19 修订日期:2021-03-05
中文摘要: 以2A12铝合金为基础材料,研究莫来石晶须对2A12铝合金组织和性能的影响。采用井式电阻炉加热,在石墨坩埚中熔炼合金,向液态金属中加入莫来石晶须,获得新合金铸态试样。用万能试验机、硬度仪测试其力学性能,用OM、SEM、EDS、XRD表征分析了显微组织。结果表明:莫来石晶须能有效改善铸态2A12铝合金的机械性能,随着其添加量的增加,合金的抗拉强度、硬度等出现先增加后降低的变化趋势,当莫来石晶须添加量为2%时,合金的抗拉强度和硬度最佳,其抗拉强度和硬度较原始合金分别增加了8.77%、7.41%;晶须的添加使合金的断裂形式发生了改变,原始合金以脆性断裂为主,随着莫来石晶须的添加,合金的断裂形式由脆性断裂向塑性断裂转变;XRD及SEM结果表明,添加的莫来石晶须以陶瓷相聚集在晶界附近。添加晶须一方面细化了晶粒,另一方面硬质点相(陶瓷)阻碍位错滑移从而提高合金的强度和硬度。
Abstract:The effect of mullite whisker on the microstructure and properties of 2A12 aluminum alloy was studied. Mullite whiskers were added into molten metal to obtain as cast samples. The mechanical properties were tested via universal testing machine and hardness tester, and the microstructure was characterized by OM, SEM, EDS and XRD, respectively. The results show that mullite whiskers can effectively improve the mechanical properties of 2A12 aluminum alloy. With the increase of mullite whisker content, the tensile strength and hardness of 2A12 aluminum alloy increased firstly and then decreased. When the amount of mullite whisker is 2%, the tensile strength and hardness of the alloy are the highest, which increase by 8.77% and 7.41% respectively. With the addition of mullite whiskers, the fracture mode of the alloy changes from brittle fracture to plastic fracture. SEM and XRD results show that the mullite phase is agglomerated near the grain boundary. It is considered that the whisker can refine the grain size and prevent dislocation slip.
文章编号: 中图分类号:TG146.2 文献标志码:
基金项目:国家自然科学基金资助项目(51902241);西安市科技局项目(201805032YD10CG16(3));西安航空学院横向课题(2019HX013); 西安航空学院高等教育研究项目(2019GJ1001)
引用文本:
王栓强,张海鸿,赵璐,刘嘉乐,李梦琪.莫来石晶须对2A12铝合金性能和组织的影响[J].有色金属工程,2021,(10):8-13.
王栓强,张海鸿,赵璐,刘嘉乐,李梦琪.莫来石晶须对2A12铝合金性能和组织的影响[J].有色金属工程,2021,(10):8-13.