利用输出波长为1064nm、脉冲宽度为20ns的钕玻璃YAG激光，对2A02铝合金进行了表面冲击试验。通过对激光冲击处理试样的HREM高分辨像观察，分析了激光冲击2A02铝合金材料微结构中的空位现象。结果表明，考察区域在激光冲击超高应变率作用下，在形成大量位错的同时，伴随形成相应的空位；空位片成为激光冲击超高应变率形变条件下铝合金基体中的特征微结构；空位和位错的重组作用加剧了点阵畸变，引起的第三类内应力和纳晶化提高了激光冲击表面的硬度和残余压应力。
Aluminum alloy 2A02 was strengthened by laser shocking using Nd： YAG laser with 1064 nm output wave length and 20 ns short pulse. The vacancy phenomenon of microstructure of the laser shocked aluminum alloy 2A02 was analyzed via images of HREM and IFFT. The experimental results indicate that a number of vacancies are produced at the shocked area of the samples together with the formation of dislocations due to the ultrahigh strain rate of laser shocking, the vacancy pieces become the characteristic mierostructure of the aluminum alloy matrix under the condition of plastic deformation via ultrahigh strain rate of laser shocking. The reconstruction between vacancy and dislocation, which intensifys the distortion of crystalline lattice and induces the third internal stress together with the nano crystallization, improves surface hardness and residual compressive stress of the laser shocked surface.
参考文献
| [1] | Kiritani M. .Similarity and difference between fcc, bcc and hcp metals from the view point of point defect cluster formation[J].Journal of Nuclear Materials: Materials Aspects of Fission and Fusion,2000(0):41-49. |
| [2] | Ohkubo H.;Shimomura Y.;Mukouda I.;Sugio K.;Kiritani M. .Formation of vacancy clusters in deformed thin films of Al-Mg and Al-Cu dilute alloys[J].Materials Science & Engineering, A. Structural Materials: Properties, Misrostructure and Processing,2003(1/2):30-36. |
| [3] | 葛茂忠,张永康,项建云.AZ31B镁合金激光冲击强化及抗应力腐蚀研究[J].中国激光,2010(11):2925-2930. |
| [4] | 罗新民,张静文,赵广志,任旭东,张永康.激光冲击强化对2A02铝合金疲劳行为的影响[J].中国激光,2009(12):3323-3328. |
| [5] | 肖纪美.反馈与耗散结构 …物·人·事理的思考…[J].材料科学与工程学报,2007(03):325-329. |
| [6] | 罗新民,苑春智,任旭东,陈康敏,张永康.激光冲击超高应变率对钛板形变微结构的影响[J].材料热处理学报,2010(06):116-121. |
| [7] | 张凌峰,张永康,任旭东,冯爱新.激光冲击约束层和吸收层的研究[J].农业机械学报,2007(01):127-131. |
| [8] | 罗新民,马辉,张静文,张永康.激光冲击中的"应变屏蔽"和"约束击穿"[J].材料导报,2010(05):11-15. |
| [9] | 李士燕,刘秀芝,何力力.深冷处理对轴承稳定性影响的研究[J].甘肃工业大学学报,2001(02):17-19. |
| [10] | X. L. Wu;B. Li;E. Ma .Vacancy clusters in ultrafine grained Al by severe plastic deformation[J].Applied physics letters,2007(14):141908-1-141908-3-0. |
| [11] | 黄丹,陶伟明,郭乙木.分子动力学模拟单晶纳米铝丝的拉伸破坏[J].兵器材料科学与工程,2005(03):1-4. |
| [12] | 石德珂.材料科学基础[M].北京:机械工业出版社,2003:97. |
| [13] | GU Qiang;WANG Yuexia;WANG Baoyi;WANG Tianmin .Influence of vacancy clusters on the atomic arrangement and displacement threshold energies in Ni_3Al[J].Chinese science bulletin,1997(17):1484-1487. |
| [14] | 朱梓忠.铝中空位形成能计算时的原胞尺寸等参数效应[J].物理学报,1998(05):784-789. |
| [15] | Davis T L;Hirth J P .Nucleation rate of vacancy clusters in crystals[J].Journal of Applied Physics,1966,37(05):2112-2116. |
| [16] | 张喜燕,周世杰,贾冲,周明哲,夏宝玉.纳米结构金属的空位变形机制 --冷轧纳米结构金属镍和钴X射线衍射研究[J].重庆工学院学报,2005(03):1-4. |
| [17] | J.Z. Lu;K.Y. Luo;Y.K. Zhang .Grain refinement of LY2 aluminum alloy induced by ultra-high plastic strain during multiple laser shock processing impacts[J].Acta materialia,2010(11):3984-3994. |
| [18] | 王声波,范勇,吴鸿兴,郭大浩,戴宇生.7050航空铝合金结构材料激光冲击[J].中国激光,2004(01):125-128. |
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