Microstructure evolution in thin sheet laser welding of titanium alloy

被引:2
作者
Kumar B. [1 ]
Kebede D. [1 ]
Bag S. [1 ]
机构
[1] Department of Mechanical Engineering, Indian Institute of Technology Guwahati, Guwahati, Assam
关键词
Cooling rate microstructure; Grain size; Laser welding; Mechanical properties; Nd:YAG; Thermal analysis; Thin plate; Ti-6Al-4V alloy; α; and; β; phases;
D O I
10.1504/IJMMS.2018.092875
中图分类号
学科分类号
摘要
The effect of cooling rate on microstructural morphology and mechanical properties of laser welded thin sheet Ti6Al4V alloy is studied. The numerical investigation has been performed to predict the weld pool geometry at different heat input by pulse Nd:YAG laser. The cooling rate is estimated from simulated time-temperature history. The solidified structure is complex and may acquire various microstructural transformations with different morphology of mainly α and β phases depending upon the particular cooling rate followed. Diffusional, α'-martensitic and mixed structures are found in the welded joint. Massive diffusion-controlled α lamellae has found in the range of 52-325 K/s. Volume fraction of α'-martensitic phase in the fusion zone increases with cooling rate. It shows that the dimensional variation of α lamellae plays an important role on mechanical properties. Substantial improvement of the mechanical properties with increase in cooling rate is characterized by the volume fraction of primary α-phase and the α + β lamellae spacing. Copyright © 2018 Inderscience Enterprises Ltd.
引用
收藏
页码:203 / 229
页数:26
相关论文
共 65 条
[1]  
Abrams H., Grain size measurement by the intercept method, Metallography, 4, 1, pp. 59-78, (1971)
[2]  
Ahmed T., Rack H.J., Phase transformations during cooling in α + β titanium alloys, Materials Science and Engineering: A, 243, 1, pp. 206-211, (1998)
[3]  
Akbari M., Saedodin S., Toghraie D., Shoja-Razavi R., Kowsari F., Experimental and numerical investigation of temperature distribution and melt pool geometry during pulsed laser welding of Ti6Al4V alloy, Optics & Laser Technology, 59, 1, pp. 52-59, (2014)
[4]  
Akman E., Demir A., Canel T., Sinmazcelik T., Laser welding of Ti6Al4V titanium alloys, Journal of Materials Processing Technology, 209, 8, pp. 3705-3713, (2009)
[5]  
Amine T., Newkirk J.W., Liou F., Methodology for studying effect of cooling rate during laser deposition on microstructure, Journal of Materials Engineering and Performance, 24, 8, pp. 3129-3136, (2015)
[6]  
Bag S., De A., Development of a three-dimensional heat-transfer model for the gas tungsten arc welding process using the finite element method coupled with a genetic algorithm-based identification of uncertain input parameters, Metallurgical and Materials Transactions A, 39, 11, pp. 2698-2710, (2008)
[7]  
Bag S., De A., Error analysis of forward and reverse heat conduction and convection calculations considering uncertainties in welding, Science and Technology of Welding and Joining, 14, 7, pp. 662-668, (2009)
[8]  
Bag S., Kiran D.V., Syed A.A., De A., Efficient estimation of volumetric heat source in fusion welding process simulation, Welding in the World, 56, 11, (2012)
[9]  
Bag S., Trivedi A., De A., Use of a multivariate optimization algorithm to develop a self-consistent numerical heat transfer model for laser spot welding, The International Journal of Advanced Manufacturing Technology, 38, 5-6, (2008)
[10]  
Bag S., Trivedi A., De A., Development of a finite element based heat transfer model for conduction mode laser spot welding process using an adaptive volumetric heat source, International Journal of Thermal Sciences, 48, 10, pp. 1923-1931, (2009)