本文主要研究内容
作者吕界(2019)在《内生Mg2Si颗粒增强铝基复合材料组织与性能的研究》一文中研究指出:相比于通常使用的钢铁材料,铝合金因具有质量轻、比强度高、耐蚀性和成型性好、成本低及可重复回收利用等优点,广泛应用于交通运输、航天航空、兵器工业和电子电气等领域。通过原位结晶法制备的Mg2Si颗粒增强铝基复合材料,具有界面洁净无污染、热稳定性好、与基体相容性好、高比强度、高比刚度以及制备成本低等优点,已成为铝基复合材料中的一个重要发展方向,具有广泛的应用。但传统铸造工艺制备的初生Mg2Si相通常为分布不均匀的粗大树枝晶,共晶Mg2Si相呈汉字状,使铝基体变得不连续,这会严重割裂铝基体,成为裂纹源,从而削弱了Al-Mg-Si合金的力学性能,阻碍了这种材料的应用。为改善Mg2Si相的形貌、大小及分布,科研工作者常用的办法是变质及热处理。已有研究表明通过添加单一合金元素及两种合金元素均能对初生Mg2Si相产生细化效果,进一步的固溶和时效处理可钝化多边形初生Mg2Si相的尖角和改善汉字状共晶Mg2Si相的形貌。总的来说,只要选择合适的复合变质剂,其变质效果通常优于单一变质剂,所以为了更好地改善内生颗粒增强铝基复合材料中Mg2Si相的尺寸和形貌,今后的研究将集中在复合变质上。因此,本论文研究了Bi-Sb复合变质、Cu-P变质及热处理对Al-20wt.%Mg2Si复合材料的组织和力学性能的影响,并探究了其中的机理,其目的是为了找到改善Al-Mg2Si复合材料中Mg2Si相的简便有效的处理工艺。研究结果总结如下:(1)在Al-20wt.%Mg2Si复合材料中单独添加0.2wt.%Bi或2wt.%Sb,均能使初生Mg2Si相由粗大树枝晶转变为多边形颗粒,平均尺寸由130.85μm分别降至21.30μm和20.46μm,且它们均使汉字状共晶Mg2Si相的片层间距缩小;试验材料的布氏硬度值由HB 94.53分别提升至HB 123.11和HB 128.10;(2)Al-20wt.%Mg2Si复合材料经0.2wt.%Bi-2wt.%Sb复合变质后,初生Mg2Si相尺寸降至10.21μm,使得布氏硬度值增至HB 130.25,极限抗拉强度和延伸率分别由未变质的216.41MPa和1.51%增至257.24MPa和2.11%。Bi-Sb复合变质的变质机理是优先生成的Mg3Sb2及AlSb化合物作为初生Mg2Si相的异质核心,细化了增强颗粒尺寸;而Bi元素吸附于Mg2Si相特定晶面,抑制了其优先生长,改善了增强颗粒形貌;(3)经6.9wt.%Cu-P变质处理后,Al-20wt.%Mg2Si复合材料中初生Mg2Si相由82.80μm降至8.95μm,使得其布氏硬度、极限抗拉强度和延伸率都有所提升,分别为HB 155.53,227.36MPa和1.74%。其变质机理是AlP的优先形成使得初生Mg2Si异质核心增多。此外,初生Mg2Si立体形貌由树枝晶转变为截断八面体。但Cu-P含量的增加使得更多Al2Cu脆性相生成,导致合金力学性能提升程度不够大;(4)固溶处理进一步改善了未变质、Bi-Sb复合变质、Cu-P变质Al-20wt.%Mg2Si复合材料的组织,其中初生Mg2Si相的棱角变得圆整,共晶Mg2Si相由汉字状变为短棒状和圆点状,从而优化了试验铝合金的显微组织,提升了其力学性能;(5)T6(500℃/24h+215℃/6h)处理不仅使Cu-P变质Al-20wt.%Mg2Si复合材料的初生及共晶Mg2Si相得到改善,还使沿晶界分布的网状Al2Cu相变得分散,提升了试验合金拉伸性能,分别为241.35MPa和2.38%。Al基体的显微维氏硬度由固溶处理后的HV 64.17增至T6处理后的HV 89.75,提升了39.85%。
Abstract
xiang bi yu tong chang shi yong de gang tie cai liao ,lv ge jin yin ju you zhi liang qing 、bi jiang du gao 、nai shi xing he cheng xing xing hao 、cheng ben di ji ke chong fu hui shou li yong deng you dian ,an fan ying yong yu jiao tong yun shu 、hang tian hang kong 、bing qi gong ye he dian zi dian qi deng ling yu 。tong guo yuan wei jie jing fa zhi bei de Mg2Sike li zeng jiang lv ji fu ge cai liao ,ju you jie mian jie jing mo wu ran 、re wen ding xing hao 、yu ji ti xiang rong xing hao 、gao bi jiang du 、gao bi gang du yi ji zhi bei cheng ben di deng you dian ,yi cheng wei lv ji fu ge cai liao zhong de yi ge chong yao fa zhan fang xiang ,ju you an fan de ying yong 。dan chuan tong zhu zao gong yi zhi bei de chu sheng Mg2Sixiang tong chang wei fen bu bu jun yun de cu da shu zhi jing ,gong jing Mg2Sixiang cheng han zi zhuang ,shi lv ji ti bian de bu lian xu ,zhe hui yan chong ge lie lv ji ti ,cheng wei lie wen yuan ,cong er xiao ruo le Al-Mg-Sige jin de li xue xing neng ,zu ai le zhe chong cai liao de ying yong 。wei gai shan Mg2Sixiang de xing mao 、da xiao ji fen bu ,ke yan gong zuo zhe chang yong de ban fa shi bian zhi ji re chu li 。yi you yan jiu biao ming tong guo tian jia chan yi ge jin yuan su ji liang chong ge jin yuan su jun neng dui chu sheng Mg2Sixiang chan sheng xi hua xiao guo ,jin yi bu de gu rong he shi xiao chu li ke dun hua duo bian xing chu sheng Mg2Sixiang de jian jiao he gai shan han zi zhuang gong jing Mg2Sixiang de xing mao 。zong de lai shui ,zhi yao shua ze ge kuo de fu ge bian zhi ji ,ji bian zhi xiao guo tong chang you yu chan yi bian zhi ji ,suo yi wei le geng hao de gai shan nei sheng ke li zeng jiang lv ji fu ge cai liao zhong Mg2Sixiang de che cun he xing mao ,jin hou de yan jiu jiang ji zhong zai fu ge bian zhi shang 。yin ci ,ben lun wen yan jiu le Bi-Sbfu ge bian zhi 、Cu-Pbian zhi ji re chu li dui Al-20wt.%Mg2Sifu ge cai liao de zu zhi he li xue xing neng de ying xiang ,bing tan jiu le ji zhong de ji li ,ji mu de shi wei le zhao dao gai shan Al-Mg2Sifu ge cai liao zhong Mg2Sixiang de jian bian you xiao de chu li gong yi 。yan jiu jie guo zong jie ru xia :(1)zai Al-20wt.%Mg2Sifu ge cai liao zhong chan du tian jia 0.2wt.%Bihuo 2wt.%Sb,jun neng shi chu sheng Mg2Sixiang you cu da shu zhi jing zhuai bian wei duo bian xing ke li ,ping jun che cun you 130.85μmfen bie jiang zhi 21.30μmhe 20.46μm,ju ta men jun shi han zi zhuang gong jing Mg2Sixiang de pian ceng jian ju su xiao ;shi yan cai liao de bu shi ying du zhi you HB 94.53fen bie di sheng zhi HB 123.11he HB 128.10;(2)Al-20wt.%Mg2Sifu ge cai liao jing 0.2wt.%Bi-2wt.%Sbfu ge bian zhi hou ,chu sheng Mg2Sixiang che cun jiang zhi 10.21μm,shi de bu shi ying du zhi zeng zhi HB 130.25,ji xian kang la jiang du he yan shen lv fen bie you wei bian zhi de 216.41MPahe 1.51%zeng zhi 257.24MPahe 2.11%。Bi-Sbfu ge bian zhi de bian zhi ji li shi you xian sheng cheng de Mg3Sb2ji AlSbhua ge wu zuo wei chu sheng Mg2Sixiang de yi zhi he xin ,xi hua le zeng jiang ke li che cun ;er Biyuan su xi fu yu Mg2Sixiang te ding jing mian ,yi zhi le ji you xian sheng chang ,gai shan le zeng jiang ke li xing mao ;(3)jing 6.9wt.%Cu-Pbian zhi chu li hou ,Al-20wt.%Mg2Sifu ge cai liao zhong chu sheng Mg2Sixiang you 82.80μmjiang zhi 8.95μm,shi de ji bu shi ying du 、ji xian kang la jiang du he yan shen lv dou you suo di sheng ,fen bie wei HB 155.53,227.36MPahe 1.74%。ji bian zhi ji li shi AlPde you xian xing cheng shi de chu sheng Mg2Siyi zhi he xin zeng duo 。ci wai ,chu sheng Mg2Sili ti xing mao you shu zhi jing zhuai bian wei jie duan ba mian ti 。dan Cu-Phan liang de zeng jia shi de geng duo Al2Cucui xing xiang sheng cheng ,dao zhi ge jin li xue xing neng di sheng cheng du bu gou da ;(4)gu rong chu li jin yi bu gai shan le wei bian zhi 、Bi-Sbfu ge bian zhi 、Cu-Pbian zhi Al-20wt.%Mg2Sifu ge cai liao de zu zhi ,ji zhong chu sheng Mg2Sixiang de leng jiao bian de yuan zheng ,gong jing Mg2Sixiang you han zi zhuang bian wei duan bang zhuang he yuan dian zhuang ,cong er you hua le shi yan lv ge jin de xian wei zu zhi ,di sheng le ji li xue xing neng ;(5)T6(500℃/24h+215℃/6h)chu li bu jin shi Cu-Pbian zhi Al-20wt.%Mg2Sifu ge cai liao de chu sheng ji gong jing Mg2Sixiang de dao gai shan ,hai shi yan jing jie fen bu de wang zhuang Al2Cuxiang bian de fen san ,di sheng le shi yan ge jin la shen xing neng ,fen bie wei 241.35MPahe 2.38%。Alji ti de xian wei wei shi ying du you gu rong chu li hou de HV 64.17zeng zhi T6chu li hou de HV 89.75,di sheng le 39.85%。
论文参考文献
论文详细介绍
论文作者分别是来自西南大学的吕界,发表于刊物西南大学2019-09-24论文,是一篇关于复合材料论文,复合变质论文,热处理论文,显微组织论文,力学性能论文,西南大学2019-09-24论文的文章。本文可供学术参考使用,各位学者可以免费参考阅读下载,文章观点不代表本站观点,资料来自西南大学2019-09-24论文网站,若本站收录的文献无意侵犯了您的著作版权,请联系我们删除。