hermal self-compressing bonding (TSCB) is a new solid-state bonding method pioneered by the authors. With electron beam as the non-melted heat source, previous experimental study performed on titanium alloys has proved the feasibility of TSCB. However, the thermal stress-strain process during bonding, which is of very important significance in revealing the mechanism of TSCB, was not analysed. In this paper, finite element analysis method is adopted to numerically study the thermal elasto-plastic stress-strain cycle of thermal self-compressing bonding. It is found that due to the localized heating, a non-uniform temperature distribution is formed during bonding, with the highest temperature existed on the bond interface. The expansion of high temperature materials adjacent to the bond interface are restrained by surrounding cool materials and rigid restraints, and thus an internal elasto-plastic stress-strain field is developed by itself which makes the bond interface subjected to thermal compressive action. This thermal self-compressing action combined with the high temperature on the bond interface promotes the atom diffusion across the bond interface to produce solid-state joints. Due to the relatively large plastic deformation, rigid restraint TSCB obtains sound joints in relatively short time compared to diffusion bonding.
Yun-Hua Deng
,
Qiao Guan
,
Jun Tao
,
Bing Wu
. Numerical Study on the Stress-Strain Cycle of Thermal Self-Compressing Bonding[J]. Chinese Journal of Mechanical Engineering, 2018
, 31(4)
: 70
-70
.
DOI: 10.1186/s10033-018-0266-x
hermal self-compressing bonding (TSCB) is a new solid-state bonding method pioneered by the authors. With electron beam as the non-melted heat source, previous experimental study performed on titanium alloys has proved the feasibility of TSCB. However, the thermal stress-strain process during bonding, which is of very important significance in revealing the mechanism of TSCB, was not analysed. In this paper, finite element analysis method is adopted to numerically study the thermal elasto-plastic stress-strain cycle of thermal self-compressing bonding. It is found that due to the localized heating, a non-uniform temperature distribution is formed during bonding, with the highest temperature existed on the bond interface. The expansion of high temperature materials adjacent to the bond interface are restrained by surrounding cool materials and rigid restraints, and thus an internal elasto-plastic stress-strain field is developed by itself which makes the bond interface subjected to thermal compressive action. This thermal self-compressing action combined with the high temperature on the bond interface promotes the atom diffusion across the bond interface to produce solid-state joints. Due to the relatively large plastic deformation, rigid restraint TSCB obtains sound joints in relatively short time compared to diffusion bonding.
[1] G I Nesterenko, B G Nesterenko. Ensuring structural damage tolerance of Russian aircraft. International Journal of Fatigue, 2009, 31(6): 1054-1061.
[2] R Dilger, H Hickethier, M D Greenhalgh. Eurofighter a safe life aircraft in the age of damage tolerance. International Journal of Fatigue, 2009, 31(6): 1017-1023.
[3] Z Huda, P Edi. Materials selection in design of structures and engines of supersonic aircrafts: A review. Materials & Design, 2013, 46: 552-560.
[4] J C Williams, E A Starke. Progress in structural materials for aerospace systems. Acta Materialia, 2003, 51(19): 5775-5799.
[5] Z Huda, T Zaharinie, G J Min. Temperature effects on material behavior of aerospace aluminum alloys for subsonic and supersonic aircrafts. Journal of Aerospace Engineering, 2010, 23(2): 124-128.
[6] S Kou. Welding metallurgy. New Jersey: John Wiley & Sons, 2003.
[7] Z X Li, H Wang, Y Li, et al. Progress on effect of processes and microelements on liquation cracking of weld heat-affected zone of nickel-based alloy. Journal of Mechanical Engineering, 2016, 52(6): 37-45. (in Chinese)
[8] X Z Chen, Y C Huang, Z Shen, et al. Effect of thermal cycle on microstructure and mechanical properties of CLAM steel weld CGHAZ. Science and Technology of Welding and Joining, 2013, 18(4): 272-278.
[9] J Liu, X L Gao, L J Zhang, et al. Effects of the heterogeneity in the electron beam welded joint on mechanical properties of Ti6Al4V alloy. Journal of Materials Engineering and Performance, 2014, 20(1): 319-328.
[10] J Ma, Z H Zhao, B H Nie, et al. Research on very high cycle fatigue behavior of the electron beam weldment for TC21 titanium alloy. Journal of Mechanical Engineering, 2015, 51(12): 68-75. (in Chinese)
[11] F Liu, Y H Hwang, S W Nam. The effect of post weld heat treatment on the creep-fatigue behavior of gas tungsten arc welded 308L stainless steel. Materials Science and Engineering A, 2006, 427: 35-41.
[12] G Thomas, V Ramachandra, R Ganeshan. Effect of pre- and post-weld heat treatments on the mechanical properties of electron beam welded Ti-6AI-4V alloy. Journal of Materials Science, 1993, 28(18): 4892-4899.
[13] X Cao, B Rivaux, M Jahazi, et al. Effect of pre- and post-weld heat treatment on metallurgical and tensile properties of Inconel 718 alloy butt joints welded using 4 kW Nd:YAG laser. Journal of Materials Science, 2009, 44(17): 4557-4571.
[14] H J Liu, X L Feng. Study of diffusion bonding of fine grain TC21 titanium alloy. Rare Metal Materials and Engineering, 2009, 38(9): 1509-1513.
[15] S D Meshram, T Mohandas. A comparative evaluation of friction and electron beam welds of near-α titanium alloy. Materials & Design, 2010, 31: 2245-2252.
[16] S M O Tavares, J F Santos, P M S T Castro. Friction stir welded joints of Al-Li Alloys for aeronautical applications: butt-joints and tailor welded blanks. Theoretical and Applied Fracture Mechanics, 2013, 65(65): 8-13.
[17] B Kurt, N Orhan, E Evin, et al. Diffusion bonding between Ti-6Al-4V alloy and ferritic stainless steel. Materials Letters, 2007, 61(8-9): 1747-1750.
[18] S J Li, J J Zhang, X B Liang, et al. Joining of carbon fibre reinforced SiC (Cf/SiC) to Ni-based superalloy with multiple interlayers. International Journal of Modern Physics B, 2003, 17 (08n09): 1777-1781.
[19] Y H Deng, Q Guan, B Wu, et al. Study on rigid restraint thermal self-compressing bonding-A new solid state bonding method. Materials Letters, 2014, 129: 43-45.
[20] Y H Deng, Q Guan, B Wu, et al. A comparative study on electron beam welding and rigid restraint thermal self-compressing bonding for Ti6Al4V alloy. Vacuum, 2015, 117: 17-22.
[21] Y H Deng, Q Guan. Rigid restraint thermal self-compressing bonding of pure titanium to titanium alloy. Materials Letters, 2015, 146: 1-3.
[22] K C Mills. Recommended values of thermophysical properties for selected commercial alloys. London: Woodhead Publishing Limited, 2002.
[23] China Aeronautical Materials Handbook Edit Committee. China aeronautical materials handbook. Beijing: China Standard Publishing Company, 2002. (in Chinese)
[24] Y Cai. Research on superplastic tensile mechanical propertities and microstructural evolution of TC4 titanium alloy at high temperature. Nanjing: Nanjing University of Aeronautics and Astronautics, 2009. (in Chinese)
[25] Y Wang, H Y Zhao, S Wu, et al. Establishment of segmented moving double ellipsoid heat source model in electron beam welding numerical simulation. Journal of Mechanical Engineering, 2004, 40(2): 165-169. (in Chinese)
[26] P Lacki, K Adamus. Numerical simulation of the electron beam welding process. Computers & Structures, 2011, 89(1-2): 977-985.
[27] Y Luo, J H Liu, H Ye. An analytical model and tomographic calculation of vacuum electron beam welding heat source. Vacuum, 2010, 84(6): 857-863.
[28] S Rouquette, J Guo, P Le. Estimation of the parameters of a Gaussian heat source by the Levenberg-Marquardt method: Application to the electron beam welding. International Journal of Thermal Sciences, 2007, 46(2): 128-138.
[29] C Liu, B Wu, J X Zhang. Numerical investigation of residual stress in thick titanium alloy plate joined with electron beam welding. Metallurgical and Materials Transactions B, 2010, 41(5): 1129-1138.
[30] P Lacki, K Adamus, P Wieczorek. Theoretical and experimental analysis of thermo-mechanical phenomena during electron beam welding process. Computational Materials Science, 2014, 94: 17-26.
[31] Y W Shi. China materials engineering canon: materials welding engineering. Beijing: Chemical Industry Press, 2006. (in Chinese)
