采用金相显微镜和透射电子显微镜研究了含钪Al-Zn-Mg-Cu-Zr系铝合金组织的再结晶,测试了不同温度下退火1h合金的硬度.结果表明:含0.20%Sc的7xxx系铝合金(冷变形量50%)的再结晶起始温度为475℃,再结晶终了温度为525℃.合金在均匀化以及热加工过程中析出细小、弥散的二次Al,(Sc,Zr)粒子钉扎位错、亚晶界和晶界,使回复过程中的位错运动受阻,保持基体内较高的位错的密度,阻碍加热时位错重新排列呈亚晶界以及更进一步发展成大角度晶界的过程;阻碍了再结晶核心长大过程,阻碍大角度晶界的迁移,从而提高再结晶温度.
Recrystallization of a cold-rolled Al-Zn-Mg-Cu-Zr alloy with minor Sc was studied by means of optical microscopy (OM), transmission electron microscopy(TEM) and hardness test after annealing at different temperatures for l h. The results show that the start recrystallizatiom temperature of 7xxx series alloy with 0. 20% Sc is 475 ℃ and the final recrystallization temperature is 525 ℃. The higher recrystallization temperature of the Al-Zn-Mg-Cu-Zr-Sc alloy is due to the precipitation of fine and disperse Al_3 (Sc, Zr) particles in homogenization annealing of the as-cast alloy ingot and followed hot working. The dispersed Al_3(Sc, Zr) particles strongly pin dislocation, grain and subgrain boundaries, which can significantly retard the recrystallization by inhibiting the nucleation of recrystallization and migration of wide-angle grain boundaries.
参考文献
[1] | Imamnra T .Current status and trend of applicable material technology for aerospace structure[J].Journal of Japan of Light Metals,1999,49(07):302-3309. |
[2] | Lengfeld P .Microstructure and mechanical behavior of spray deposited Zn modified 7xxx series Al alloys[J].International Journal of Rapid Solidification,1995,8(04):237-265. |
[3] | Norman AF.;Hyde K.;Costello F.;Thompson S.;Birley S.;Prangnell PB. .Examination of the effect of Sc on 2000 and 7000 series aluminium alloy castings: for improvements in fusion welding[J].Materials Science & Engineering, A. Structural Materials: Properties, Misrostructure and Processing,2003(1/2):188-198. |
[4] | 戴晓元,夏长清,马科,刘娟.Sc对Al-Zn-Mg-Cu-Zr合金铸态组织和力学性能的影响[J].中国有色金属学报,2007(08):1324-1329. |
[5] | Senkov O N;Miracle D B;Milman Y V et al.Low temperature mechanical properties of scandium-modified Al-Zn-Mg-Cu alloys[J].Materials Science Forum,2002,396 -402:664-6670. |
[6] | Milman Y V;Sirko A I;Lotsko D V et al.Microstructure and mechanical properties of cast and wrought Al-Zn-Mg-Cu alloys modified with Zr and Sc[J].Materials Science Forum,2002,396 -402:1127-11132. |
[7] | YIN Zhi-min;JIANG Feng;PAN Qing-lin;GUO Fei-yue;ZHU Da-peng;SONG Lian-peng;ZEN Yu;WANG Tao .Microstructures and mechanical properties of Al-Mg and Al-Zn-Mg based alloys containing minor scandium and zirconium[J].Transactions of Nonferrous Metals Society of China,2003(3):515-520. |
[8] | 李海,杨迎新,郑子樵,王芝秀.少量Sc对7055铝合金组织与性能的影响[J].材料科学与工艺,2006(01):46-49. |
[9] | Miura Y;Shioyama O;Hara D .RecrystaUization of Al-3Mg and Al-3Mg-0.2Sc alloys[J].Materials Science Forum,1996,217 -222:505-5510. |
[10] | Dougherty L M;Robertson I M;Vetrano J S .Direct observation of the behavior of grain boundaries during continuous dynamic rocrystallization in an Al-4Mg-0.3Sc alloy[J].Acta Materialia,2003,51:4367-44378. |
[11] | YU Kun;LI Wen-xian;LI Song-rui et al.Mechanical properties and microstructure of aluminum alloy 2618 with Al_3 (Sc,Zr) phase[J].Materials Science and Engineering A,2004,368:88-893. |
[12] | Vladivoj Ocenasek;Margarita Slamova .Resistance to recrystallization due to Sc and Zr addition to Al-Mg alloys[J].Materials Characterization,2001(2):157-162. |
[13] | 赵卫涛,闫德胜,戎利建.变形Al-Mg-Sc-Zr合金退火组织的TEM观察[J].金属学报,2005(11):1150-1154. |
[14] | 潘青林,尹志民,高拥政,张永红,左铁镛.Al-Mg-Sc合金的再结晶[J].中国有色金属学报,1998(03):427-430. |
[15] | 曹明盛.物理冶金基础[M].北京:冶金工业出版社,1985 |
[16] | 毛卫民;赵新兵.金属的再结晶与晶粒长大[M].北京:冶金工业出版社,1994 |
[17] | 卡恩 R W;哈森 P;克雷默 E J;雷廷权.材料科学与技术丛书[M].北京:科学出版社,1999 |
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