7A60铝合金搅拌摩擦加工组织及性能

doi:10.16183/j.cnki.jsjtu.2019.11.015

摘要/Abstract

摘要： 以7A60铝合金为研究对象，采用搅拌摩擦加工(Friction Stir Processing, FSP)技术对其进行塑性改性并探索加工参数对7A60铝合金组织及力学性能的影响.结果表明：搅拌摩擦加工过程中铝合金发生动态再结晶而形成细小均匀的等轴晶；基体中第二相破碎细化，均匀分布在基体中且组织中η(MgZn2)相发生回溶；速比因子在很大程度上影响合金性能，随着速比因子的增大，搅拌区硬度先增加后减小.当速比因子为5时，材料显微硬度和抗拉强度达到最高(维氏硬度约120，抗拉强度 449.9MPa)，相比母材分别提高 37.5% 和 35.5%；速比因子继续增大时，搅拌头产热量急剧增加，导致材料组织严重粗化且拉伸断口韧窝变浅，使得材料强度和塑性降低.

关键词: 搅拌摩擦加工； 7A60铝合金；显微组织；力学性能

Abstract: Friction stir processing (FSP) were carried out to modify the mechanical properties of 7A60 aluminum alloy. The effect of friction stir processing parameters on the microstructure and mechanical properties of 7A60 aluminum alloy were investigated. The results showed that the uniform and fine equiaxed grains were formed due to dynamic recrystallization and the second phases were refined by severe plastic deformation with homogeneous distribution in the Al matrix. Meanwhile the content of η (MgZn2) phase decreased under the action of FSP heat, indicating the occurrence of the dissolution of η(MgZn2) phase into the Al matrix. Velocity ratio factor (ω/v) was a decisive impact factor of the mechanical performance of the nugget zone. With the increase of ω/v, the microhardness of the FSP-processed sample firstly increased and then decreased. The highest Vickers hardness was 120, which was 37.5% higher than the base metal, was obtained when ω/v reached 5, and the tensile strength increased to 449.9MPa. With the increase of ω/v, more heat produced by the stirring head led to significant grain coarsening and the dimples of the tensile specimens fractography become shallow, which in turn severely affected the tensile strength and plasticity of the material.

Key words: friction stiring processing (FSP); 7A60 aluminum alloy; microstructure; mechanical properties

中图分类号:

TG 146

李萍，张凯，王薄笑天，薛克敏. 7A60铝合金搅拌摩擦加工组织及性能[J]. 上海交通大学学报, 2019, 53(11): 1381-1388.

LI Ping,ZHANG Kai,WANG Boxiaotian,XUE Kemin. Microstructure and Mechanical Properties of 7A60 Aluminum Alloy by Friction Stir Processing[J]. Journal of Shanghai Jiaotong University, 2019, 53(11): 1381-1388.

参考文献

［1］SONG F X, ZHANG X M, LIU S D, et al. Exfolia-tion corrosion behavior of 7050-T6 aluminum alloy treated with various quench transfer time［J］. Tran-sactions of Nonferrous Metals Society of China, 2014, 24(7): 2258-2265.

［2］高晓龙, 夏天东, 王晓军, 等. 金属晶粒细化方法的研究现状［J］.金属功能材料, 2009, 16(6): 60-65.

GAO Xiaolong, XIA Tiandong, WANG Xiaojun, et al. Present research status for metals refinement methods［J］. Metallic Founction Materials, 2009, 16(6): 60-65.

［3］杨保健, 夏琴香, 张鹏, 等. SPD制备纳米/超细晶金属材料的成形方法［J］. 锻压技术, 2011, 36(2): 48-52.

YANG Baojian, XIA Qinxiang, ZHANG Peng, et al. Forming method of ultra-fine grain/nanocrystalline metallic material based on SPD［J］. Forging & Stamping Technology, 2011, 36(2): 48-52.

［4］郑小茂, 张大童, 张文, 等. 焊接参数对7A04铝合金搅拌摩擦焊接头组织与力学性能的影响［J］. 焊接学报, 2016, 37(1): 76-80.

ZHENG Xiaomao, ZHANG Datong, ZHANG Wen, et al. Effect of welding parameters on microstructure and mechanical properties of friction stir welded joint of 7A04 aluminum alloy［J］. Transactions of The China Welding Institution, 2016, 37(1): 76-80.

［5］PATEL V V, BADHEKA V J, KUMAR A. Effect of velocity index on grain size of friction stir processed Al-Zn-Mg-Cu alloy［J］. Procedia Technology, 2016, 23: 537-542.

［6］PATEL M V, BADHEKA V, KUMAR A. Influence of friction stir processed parameters on superplasticity of Al-Zn-Mg-Cu alloy［J］. Advanced Materials & Manufacturing Processes, 2016, 31(12): 1573-1582.

［7］金玉花, 霍仁杰, 李常锋, 等. 转速对7055铝合金搅拌摩擦焊接头断裂特征的影响［J］. 焊接学报, 2017, 38(2): 10-13.

JIN Yuhua, HUO Renjie, LI Changfeng, et al. Influence of rotational speed on fracture characteristics of 7055 aluminum alloy friction stir welded joints［J］. Transactions of The China Welding Institution, 2017, 38(2): 10-13.

［8］董继红, 佟建华, 郭晓娟, 等. 30 mm 7A05铝合金搅拌摩擦焊接头组织及力学性能［J］. 焊接学报, 2012, 33(4): 65-68.

DONG Jihong, TONG Jianhua, GUO Xiaojuan, et al. Microstructure and mechanical properties of friction stir welded joint of 30 mm 7A05 aluminum alloy［J］. Transactions of The China Welding Institution, 2012, 33(4): 65-68.

［9］张鑫, 陈玉华, 王善林. 工艺参数对Ti/Zn/Al异种金属搅拌摩擦焊接头力学性能的影响［J］.稀有金属材料与程, 2017, 46(1): 247-251.

ZHANG Xin, CHEN Yuhua, WANG Shanlin. Effect of process parameters on mechanical properties of Ti/Zn/Al joint welded by friction stir welding［J］. Rare Metal Materials And Engineering, 2017, 46(1): 247-251.

［10］王海艳, 戚文军, 农登, 等. 6061铝合金搅拌摩擦焊接头组织与性能研究［J］.稀有金属, 2010, 34(5): 638-642.

WANG Haiyan, QI Wenjun, NONG Deng, et al. Microstructure and properties of friction stir welding 6061 aluminium alloy joint［J］. Chinese Journal of Rare Metals, 2010, 34(5): 638-642.

［11］SAUVAGE X, MURASHKIN M Y, STRAUMAL B B, et al. Ultrafine grained structures resulting from SPD-induced phase transformation in Al-Zn alloys［J］. Advanced Engineering Materials, 2015, 17(12): 1821-1827.

［12］张显峰, 陆政, 赵钊, 等. 挤压态7A85铝合金高温热变形显微组织演变［J］.湖南大学学报(自然科学版), 2017, 44(6): 7-11.

ZHANG Xianfeng, LU Zheng, ZHAO Zhao, et al. Microstructure evolution of as-extruded 7A85 aluminum alloy during high temperature deformation［J］. Journal of Hunan University (Natural Sciences), 2017, 44(6): 7-11.

［13］HUANG R, HAN Y. Structure evolution and thermal stability of SMAT-derived nanograined layer on Ti-25Nb-3Mo-3Zr-2Sn alloy at elevated temperatures［J］. Journal of Alloys & Compounds, 2013, 554: 1-11.

［14］TOPPING T D, AHN B, LI Y, et al. Influence of process parameters on the mechanical behavior of an ultrafine-grained Al alloy［J］. Metallurgical & Materials Transactions A, 2012, 43(2): 505-519.

［15］MAVLYUTOV A M, KASATKIN I A, MURASHKIN M Y, et al. Influence of the microstructure on the physicomechanical properties of the aluminum alloy Al-Mg-Si nanostructured under severe plastic deformation ［J］. Physics of the Solid State, 2015, 57(10): 2051-2058."

[1]	吴松波,蔡振兵,林禹,王璋,刘新龙,朱旻昊. 沙粒粒径对TC4钛合金冲击界面损伤行为的影响[J]. 上海交通大学学报（自然版）, 2018, 52(5): 568-574.
[2]	余廷1, 2, 邓琦林1, 张伟3, 董刚4, 杨建国1. 激光熔覆NiCrBSi合金涂层的裂纹形成机理 [J]. 上海交通大学学报（自然版）, 2012, 46(07): 1043-1048.
[3]	季媛媛，董纪伟，冯淼林. 循环应变下多晶铜非Massing现象的模拟[J]. 上海交通大学学报（自然版）, 2010, 44(01): 21-0024.
[4]	张克伟1，佘欢2，刘宏亮2，疏达2，王俊2. Si含量对高强高韧7050铝合金组织和力学性能的影响[J]. 上海交通大学学报（自然版）, 2013, 47(11): 1712-1716.
[5]	张金玲1,3，张明义1，张嘉振1，崔振山2,周振功3. 晶界原子尺度运动机制的研究进展[J]. 上海交通大学学报（自然版）, 2014, 48(03): 388-393.
[6]	李振华1，马彩云1,华晨2，程先华2,3. 等径角挤压工艺对Ti5553合金冲蚀磨损性能的影响[J]. 上海交通大学学报（自然版）, 2015, 49(01): 37-43.