Exploring the Formation Mechanism of Aluminum/Steel Resistance Spot Welding Joint Assisted by Ultrasonic Vibration

doi:10.3901/JME.2024.22.139

Abstract

Abstract: In order to improve the quality of aluminum/steel spot welded joints, ultrasonic longitudinal vibration is introduced into the conventional resistance spot welding(RSW) process. Considering joint microstructure analysis, welding process energy analysis, and the results of finite element numerical calculations, the nugget formation mechanism of ultrasonic vibration-assisted resistance spot welding(UA-RSW) of aluminum/steel welded joint is determined. Subsequently, a comprehensive analysis of interfacial compounds, welding defects, microhardness, and joint strength characteristics during UA-RSW of aluminum/steel joints is conducted. The results demonstrate a significant reduction in the sizes of the aluminum/steel double nugget after the introduction of ultrasonic vibration. This reduction is a result of competing of multiple ultrasonic effects, where ultrasonic vibrations reduce the contact resistance between sheets. Additionally, the electrical of molten steel and thermal conductivities of molten aluminum increase due to acoustic cavitation and acoustic flow effects. Moreover, ultrasonic vibration increases the bulge height of the steel sheet, promotes the radial creep of molten aluminum and near-molten aluminum, expanding the effective bonding area between aluminum and steel sheets. Ultrasonic vibration also effectively reduces the thickness of the intermetallic compound(IMC) layer to less than 3.0 μm in thickness and inhibits the formation of interface welding defects. Tensile-shear tests demonstrate that ultrasonic longitudinal vibration can achieve an aluminum button pull-out failure mode, increasing its peak tensile-shear load by 48.68% compared with the conventional RSW process.

Key words: ultrasonic vibration, resistance spot welding, aluminum/steel, microstructure, evolution of double nuggets

CLC Number:

TG457

Ren Baokai, Zhou Kang, Wang Gang. Exploring the Formation Mechanism of Aluminum/Steel Resistance Spot Welding Joint Assisted by Ultrasonic Vibration[J]. Journal of Mechanical Engineering, 2024, 60(22): 139-152.

References

[1] 李永兵，马运五，楼铭，等. 轻量化薄壁结构点连接技术研究进展[J]. 机械工程学报，2020，56(6)：125-146. LI Yongbing，MA Yunwu，LOU Ming，et al. Advances in spot joining technologies of lightweight thin-walled structures[J]. Journal of Mechanical Engineering，2020，56(6)：125-146.
[2] 李永兵，马运五，楼铭，等. 轻量化多材料汽车车身连接技术进展[J]. 机械工程学报，2016，52(24)：1-23. LI Yongbing，MA Yunwu，LOU Ming，et al. Advances in welding and joining processes of multi-material lightweight car body[J]. Journal of Mechanical Engineering，2016，52(24)：1-23.
[3] PAN Bo，SUN Hui，SHANG Shunli，et al. Understanding formation mechanisms of intermetallic compounds in dissimilar Al/steel joint processed by resistance spot welding[J]. Journal of Manufacturing Processes，2022，83：212-222.
[4] 谢泽豪，李建宇，陈树海，等. 钢/铝异种金属点焊研究进展[J]. 航空学报，2022，43(2)：625118. XIE Zehao，LI Jianyu，CHEN Shuhai，et al. Research progress in steel/Al-alloys dissimilar metals spot welding[J]. Acta Aeronautica et Astronautica Sinica，2022，43(2)：625118.
[5] ZHANG Guotao，ZHAO Hang，XU Xianghe，et al. Metallic bump assisted resistance spot welding (MBaRSW) of AA6061-T6 and bare DP590：Part I-printing of metallic bump[J]. Journal of Manufacturing Processes，2019，44：427-434.
[6] CHEN Nannan，WANG Huiping，WANG Min，et al. Schedule and electrode design for resistance spot weld bonding Al to steels[J]. Journal of Materials Processing Technology，2019，265：158-172.
[7] LU Ying，WALKER L，KIMCHI M，et al. Microstructure and strength of ultrasonic plus resistance spot welded aluminum alloy to coated press hardened boron steel[J]. Metallurgical and Materials Transactions A，2020，51A(1)：93-98.
[8] LI Mingfeng，TAO Wu，ZHANG Jiazhi，et al. Hybrid resistance-laser spot welding of aluminum to steel dissimilar materials：Microstructure and mechanical properties[J]. Materials and Design，2022，221：111022.
[9] BAEK S，GO G Y，PARK J，et al. Microstructural and interface geometrical influence on the mechanical fatigue property of aluminum/high-strength steel lap joints using resistance element welding for lightweight vehicles：Experimental and computational investigation[J]. Journal of Materials Research Technology，2022，17：658-678.
[10] ZHOU Kang，REN Baokai，YU Wenxiao. Optimized designing of generalized electrodes for aluminum/steel resistance spot welding process based on numerical calculation[J]. Journal of Manufacturing Processes，2023，99：563-580.
[11] HU Shanqing，HASEHUHN A，MA Yunwu，et al. Comparison of the resistance spot weldability of AA5754 and AA6022 aluminum to steels[J]. Welding Journal，2020，99(8)：224S-238S.
[12] LOU Ming，NIU Sizhe，MA Yunwu，et al. The aging characteristics of resistance rivet welded aluminum/steel joints[J]. Journal of Materials Research Technology，2023，26：3615-3628.
[13] HU Shanqing，HASEHUHN A，MA Yunwu，et al. Effect of external magnetic field on resistance spot welding of aluminium to steel[J]. Science and Technology of Welding and Joining，2022，27(2)：84-91.
[14] SHAH U，LIU Xun. Effects of ultrasonic vibration on resistance spot welding of transformation induced plasticity steel 780 to aluminum alloy AA6061[J]. Materials and Design，2019，182：108053.
[15] WAN Zixuan，WANG Huiping，WANG Min，et al. Numerical simulation of resistance spot welding of Al to zinc-coated steel with improved representation of contact interactions[J]. International Journal of Heat Mass Transfer，2016，101：749-763.
[16] BAI Yang，YANG Ming. The influence of superimposed ultrasonic vibration on surface asperities deformation[J]. Journal of Materials Processing Technology，2016，229：367-374.
[17] ABED A M，JASIM S A，LASHIN M M，et al. The characterization of cold welding process in CuZr metallic glasses with dissimilar alloying compositions[J]. Materials Today Communications，2022，31：103471.
[18] LE Q，LAN Q，ZHANG Jianfeng，et al. Effects of ultrasonic field on the Pb-Sn alloys during heating process[J]. Materialwissenschaft und Werkstofftechnik，2018，49(7)：928-933.
[19] LIU Xuan，ZHANG Jianfeng，LI Haoyu，et al. Electrical resistivity behaviors of liquid Pb-Sn binary alloy in the presence of ultrasonic field[J]. Ultrasonics，2015，55：6-9.
[20] DEHBANI M，RAHIMI M，RAHIMI Z. A review on convective heat transfer enhancement using ultrasound[J]. Applied Thermal Engineering，2022，208：118273.
[21] PECHA R，GOMPF B. Microimplosions：Cavitation collapse and shock wave emission on a nanosecond time scale[J]. Physical Review Letters，2000，84(6)：1328.
[22] LEPESHKIN A，SHCHERBAKOV P. Investigation of thermal conductivity of metal materials on view of influence of ultrasonic waves[C]//proceedings of the Journal of Physics：Conference Series，F，2017. IOP Publishing.
[23] LEGAY M，GONDREXON N，LE P S，et al. Enhancement of heat transfer by ultrasound：Review and recent advances[J]. International Journal of Chemical Engineering，2011，2011：670108.
[24] BULLIARD O，FERROUILLAT S，VIGNAL L，et al. Heat transfer enhancement using 2 MHz ultrasound[J]. Ultrasonics Sonochemistry，2017，39：262-271.
[25] LI Junwen，MOMONO T，YING F，et al. Effect of ultrasonic stirring on temperature distribution and grain refinement in Al-1.65% Si alloy melt[J]. Transactions of Nonferrous Metals Society of China，2007，17(4)：691-697.
[26] DANGI B，BROWN T，KULKARNI K. Effect of silicon，manganese and nickel present in iron on the intermetallic growth at iron-aluminum alloy interface[J]. Journal of Alloys Compounds，2018，769：777-787.
[27] NIU Sizhe，MA Yunwu，LOU Ming，et al. Joint formation mechanism and performance of resistance rivet welding (RRW) for aluminum alloy and press hardened steel[J]. Journal of Materials Processing Technology，2020，286：116830.