中国激光, 2020, 47 (5): 0502006, 网络出版: 2020-05-12
激光冲击与喷丸复合强化对TC4钛合金细节疲劳额定强度截止值DFRcutoff的影响 下载: 1225次
Cut-Off Value of Detail Fatigue Rated Strength of TC4 Titanium Alloy with Compound Strengthening Treatment by Laser Shock Peening and Shot Peening
激光技术 TC4钛合金 喷丸强化 激光冲击强化 复合强化 DFRcutoff 残余应力 laser technique TC4 titanium alloy shot peening laser shock peening compound strengthening cut-off value of detail fatigue rated strength residual stress
摘要
为研究激光冲击与喷丸复合强化对TC4钛合金疲劳性能的影响,在测试不同强化工艺状态(未强化状态、喷丸强化状态、激光冲击强化状态、激光冲击与喷丸复合强化状态)TC4钛合金表面残余应力的基础上,进行了细节疲劳额定强度截止值(DFRcutoff)试验,并利用ABAQUS有限元仿真分析其表层残余应力分布。试验结果表明:复合强化TC4钛合金的表面残余压应力和DFRcutoff最大,相比于未强化状态分别提高了189.1%和62.3%。仿真结果表明:表面处理会在试样表面形成残余压应力,激光冲击与喷丸复合强化状态试样的表面残余压应力最大,喷丸强化试样的次之,激光冲击强化试样的最小;激光冲击与喷丸复合强化试样中的残余压应力层最深,激光冲击强化试样的次之,喷丸强化试样的最浅。结合试验结果与有限元分析可知,TC4钛合金的DFRcutoff与表面残余压应力和残余压应力层深度呈正相关。
Abstract
To study the fatigue properties of TC4 titanium alloy subjected to compound strengthening treatment by laser shock peening and shot peening, surface residual stress and cut-off value of detail fatigue rated strength (DFRcutoff) were measured for TC4 titanium alloy for various surface-strengthening cases. These cases included untreated state, shot peening, laser shock peening, and compound strengthening by shot peening and laser shock peening. Additionally, the distribution of residual stress was analyzed by ABAQUS software. Test results show that samples treated by compound strengthening exhibit the highest values of both the surface residual compressive stress and DFRcutoff, with an increment of 189.1% and 62.3% over those of untreated samples, respectively. Simulation results indicate that residual compressive stress can form on the sample surface after the strengthening process, and the surface residual compressive stress on the compound-strengthened surface is the highest, followed by the samples subjected to shot peening and laser shock peening. Moreover, the residual compressive stress layer created by the compound strengthening treatment is the deepest, followed by that for laser shock peening and finally shot peening. From the combined results of tests and finite element analysis, it can be concluded that the DFRcutoff of TC4 titanium alloy is positively correlated with the surface residual compressive stress and depth of the residual compressive stress layer.
刘亚鹏, 史志俊, 赵一昭, 朱亮, 刘马宝. 激光冲击与喷丸复合强化对TC4钛合金细节疲劳额定强度截止值DFRcutoff的影响[J]. 中国激光, 2020, 47(5): 0502006. Yapeng Liu, Zhijun Shi, Yizhao Zhao, Liang Zhu, Mabao Liu. Cut-Off Value of Detail Fatigue Rated Strength of TC4 Titanium Alloy with Compound Strengthening Treatment by Laser Shock Peening and Shot Peening[J]. Chinese Journal of Lasers, 2020, 47(5): 0502006.