Effect of Process Parameters on Microstructure and Dynamic Compressive Property of Ti-6Al-4V Plates Fabricated via Friction Stir Welding
The microstructure and mechanical properties of Ti-6Al-4V plates (thickness: 5 mm) welded via friction stir welding (rotation speed: 150-300 rpm, welding speed: 70-100 mm/min) were investigated. The microstructural investigation revealed that the nugget obtained at 150 rpm and 70 mm/min was composed of a mixed structure, whereas the other weld joints were composed of a fully lamellar structure. Transmission electron microscopy analysis revealed that fine recrystallized α-grains and dislocations occurred in the lamellar structure. The tensile tests showed that the tensile strength of all joints reached 96% of the tensile strength characterizing the base material. Moreover, the failure strain of each joint during tensile testing was > 13%. The weld joints with fully lamellar nuggets exhibited better dynamic compressive properties than the joints with mixed-structure nuggets. The results demonstrated that the recrystallized α-grains and dislocations are beneficial for enhancing the dynamic mechanical properties. The optimum dynamic mechanical response was obtained when a rotation speed and welding speed of 300 rpm and 100 mm/min, respectively, were employed as the welding parameters.
Keywordsdynamic compressive property friction stir welding microstructure Ti-6Al-4V
This study is financially supported by “The National Natural Science Foundation of China (No. 51571031).” We thank Liwen Bianji, Edanz Editing China (www.liwenbianji.cn/ac), for editing the English text of a draft of this manuscript.
- 4.Y. Suyuan, Z. Hongran, T. Yishi, and Y. Ying, Microstructure and Properties of Friction Stir Welded Joints of Magnesium Rare Earth Alloy, Chin. J. Rare Met., 2013, 37(1), p 33–37Google Scholar
- 5.L. Yang Suyuan, Dongdong, Status and Prospect of Friction Stir Welding of Magnesium Alloys, Chin. J. Rare Met., 2014, 38(5), p 896–904Google Scholar
- 20.R.H. Gao, Q.B. Fan, F.C. Wang, Y.P. Zhang, L.R. Huo, and C.H. Pei, Relationship between Dynamic Compressive Mechanical Properties and Ballistic Performance of Titanium Armor Materials, Rare Met. Mater. Eng., 2015, 44(11), p 2733–2736 ((Chinese))Google Scholar
- 32.M.Q. Peng, X.W. Cheng, C. Zheng, K.W. Yang, and D. Jin, Effects of Secondary alpha Phase Width on Dynamic Mechanical Properties and Sensitivity of Adiabatic Shear Banding in Bimodal Microstructures of TC4 Alloy, Rare Metal Mater. Eng., 2017, 46(7), p 1843–1849 ((Chinese))Google Scholar