往复挤压L2纯铝的组织与性能Microstructure and mechanical properties of reciprocating extruded pure Al L2
刘礼,徐春杰,张忠明,郭学锋
摘要(Abstract)：
采用往复挤压(RE)工艺,在350℃挤压比为7.7∶1时,对工业纯铝L2进行了1道次和6道次往复挤压。结果发现,往复挤压可以改善材料的微观组织结构,显著细化晶粒,提高了组织的均匀性。然而往复挤压不能显著提高纯铝的硬度和拉伸强度。这是由于往复挤压过程中发生动态回复,极大地降低纯铝的位错密度,使材料软化,抵消了细晶强化作用。同时由于晶粒的细化和位错密度的降低,往复挤压提高了纯铝的延伸率。与室温等径转角挤压(ECAP)相比,350℃RE工艺可以提高工业纯铝L2的延展性,但对纯铝的细化效果不如ECAP。
关键词(KeyWords)： 往复挤压(RE);纯铝L2;位错密度
基金项目(Foundation): 国家自然科学基金(50271054);; 教育部回国留学人员重点基金;; 陕西省自然科学基金(2002E110);; 凝固技术国家重点实验室基金(200301)
作者(Author): 刘礼,徐春杰,张忠明,郭学锋
参考文献(References)：
- [1]Terhune S D,swisher D L,Oh-ishi K,et al.An investigation of microstructure and grain-boundary evolution during ECA pressing of pure aluminum[J].Metallurgical and Materials Transactions A,2002,33A:2173-2183.
- [2]Dong H S,Kim I,Kim J,et al.Grain refinement mechanism during equal-channel angular pressing of low-carbon steel[J].Acta Mater,2001,49:1285-1292.
- [3]Chu H S,Liu K S,Yeh J W.Study of 6061-Al2O3p composites produced by reciprocating extrusion[J].Metallurgical and Materials Transactions A,2000,31A(10):2587-2596.
- [4]Chu H S,Liu K S,Yeh J W.An in situ composite of Al(graphite,Al4C3)produced by reciprocating extrusion[J].Materials Science and Engineering A,2000,277:25-32.
- [5]Lee S W,Wang H Y,Chen Y L,et al.An Mg-Al-Zn alloy with very high specific strength and superior high-strain-rate superplasticity processed byreciprocating extrusion[J].Advanced Engineering Materials,2004,6(12):948-952.
- [6]Yuan S Y,Peng C H,Yeh J W.Synthesis of fine Pb-50vol.%Sn alloys by a new process of reciprocating extrusion[J].Materials Science and Technology,1999,15:683.
- [7]Lee S W,Yeh J W,Liao Y S.Premium 7075Aluminium Alloys Produced by Reciprocating Extrusion.Advanced Engineering Materials,2004,12(6):936-943.
- [8]田景来.ECAP纯铝L2的组织与性能研究[D].西安理工大学,2005.
- [9]石德珂.位错与材料强度[M].西安:西安交通大学出版社,1988:145-147.
- [10]李永霞,张永刚,陈昌麒,等.截面通道角形挤压对高纯铝微观组织及力学性能的影响[J].航空材料学报,2001,21(3):33-38.LI Y X,ZHANG Y G,CHEN C G.Effect of equal channel angular pressing on microstructure and mechanical properties of high pure aluminum[J].Journal ofAeronautical Materials,2001,21(3),33-38.
- [11]孙佩玲.纯铝等径转角挤压之变形组织[D].台湾国立中山大学材料科学研究所,2002.
文章评论(Comment)：
|
||||||||||||||||||
|
||||||||||||||||||