Effect of defocuson performance of butt joints of pure titanium sheet
In order to study the properties of laser butt welding joint of pure titanium sheet, a welding system consisting of fiber laser and robot was used to carry out the welding test. Effect of defocus on the properties of the joint was evaluated comprehensively by testing the tensile properties, porosity and cupping value of the joint. The microstructure of the joint was revealed. The results show that the tensile and forming properties of the joints are lower than those of the base metal. The defocus has no direct effect on the tensile properties. To a certain extent, the formability of the joint increases with the increase of defocus. When the defocus is +20mm, the joint has the best tensile and forming properties. The microstructures in the weld zone are coarse α grains + serrated α grains + a small amount of acicular α grains. The existence of acicular α grains is beneficial to improve the formability of the joints. The microstructure of heat affecting zone (HAZ) is composed of irregular coarse α grains + serrated α grains. The grain size of HAZ is lower than that of weld zone. This research has certain theoretical guiding significance for laser welding of pure titanium.
【1】SHI J, WEN B B, YU Z T, et al. Influencing factors of titanium and titanium alloys shell’s stamp forming and its application status［J］. Titanium Industry Progress, 2016, 33(5):1-5 (in Chinese).
【2】XING Q L, PENG P, ZHANG Ch J, et al. Influencing factors and technology advances of titanium alloy plate in deep drawing［J］. Titanium Industry Progress, 2015, 32(4):1-7 (in Chinese).
【3】YANG J D, ZHOU Y F, YANG T, et al. Nanocrystallization of Ti-6Al-4V alloy by multiple laser shock processing［J］. Laser Technology, 2017, 41(5):754-758(in Chinese).
【4】FU M J, ZHANG T, HAN X Q, et al. Superplastic deformation be- havior of TNW700 titanium alloy sheet［J］. Chinese Journal of Rare Metals, 2016, 40(1):1-7(in Chinese).
【5】XU G D, WANG G Sh. The development of titanium metal and titanium industry［J］. Chinese Journal of Rare Metals, 2009, 33(6):903-912(in Chinese).
【6】XIAO L, SONG W, CHENG W, et al. Mechanical properties of open-cell rhombic dodecahedron titanium alloy lattice structure manufactured using electron beam melting under dynamic loading［J］. International Journal of Impact Engineering, 2017, 100:75-89.
【7】JIA X, LU F Sh, HAO B. Report on china titanium industry progress in 2016［J］. Titanium Industry Progress, 2017, 34(2):1-7(in Ch-inese).
【8】JIA X, LU F Sh, HAO B. Report on China Titanium industry progress in 2017［J］. Iron Steel Vanadium Titanium, 2018, 39(2):1-7(in Chinese).
【9】JIANG J H, DING Y, SHAN A D. Microstructure and mechanical properties of commercial purity Ti rolled at room temperature［J］. The Chinese Journal of Nonferrous Metals, 2010, 20(s1):58-61(in Ch-inese).
【10】CUI C J, PENG Q, ZHANG M J, et al. Characterization of cathodic polarization of industrial pure titanium in sea water by ac impedance technique［J］. Corrosion Science and Protection Technology, 2003, 15(6):327-330(in Chinese).
【11】ZHANG Y, SUN D Q, GU X Y, et al. A hybrid joint based on two kinds of bonding mechanisms for titanium alloy and stainless steel by pulsed laser welding［J］. Materials Letters, 2016, 185:152-155.
【12】PANWISAWAS C, PERUMAL B, WARD R M, et al. Keyhole formation and thermal fluid flow-induced porosity during laser fusion welding in titanium alloys: Experimental and modelling［J］. Acta Materialia, 2017, 126:251-263.
【13】LIU L M, SHI J P, WANG H Y. Research on the low power laser induced arc hybrid welding of titanium alloy thin sheet［J］. Journal of Mechanical Engineering, 2016, 52(18):38-43(in Chinese).
【14】PENG H S, CHEN B H, TANG J L, et al. Effect of laser welding technology on mechanical properties of K418 and 0Cr18Ni9 weld joints［J］. Laser Technology, 2018, 42(2):229-233(in Chinese).
【15】LI Zh, SHI Y, LIU J, et al. Effect of laser welding parameters on microstructure and mechanical properties of commercial pure titanium［J］. Applied Laser, 2016,36(1):53-57(in Chinese).
【16】XU W F, ZHANG Z L. Microstructure and mechanical properties of laser beam welded TC4/TA15 dissimilar joints［J］. Transactions of Nonferrous Metals Society of China, 2016, 26(12):3135-3146.
【17】LI Y, XU G X. Metallographic sample preparation and microstructure analysis of TC4 titanium alloy laser welding joints［J］. Hot Working Technology, 2016(13):187-189(in Chinese).
【18】HUANG Sh Sh, QIU Zh W. Research on mechanical properties and microstructure of laser welding joint of automotive TC15 titanium a-lloy［J］. Rare Metals and Cemented Carbides, 2017(5):46-49(in Chinese).
【19】LI B, YUAN F B, LI F N, et al. Feature analysis of coaxial monitoring of welding pool and keyhole during laser deep penetration welding［J］. Laser Technology, 2017, 41(2):255-259(in Chinese).
【20】YANG Ch Ch, XU Y L, TONG Sh, et al. Process research fiber laser welding of TC4 titanium alloy［J］. Applied Laser, 2016,36(5):543-546(in Chinese).
ZHOU Leilei. Effect of defocuson performance of butt joints of pure titanium sheet[J]. Laser Technology, 2019, 43(3): 397-400
周磊磊. 离焦量对纯钛薄板对接焊缝性能的影响[J]. 激光技术, 2019, 43(3): 397-400