Investigation of Microstructure and Corrosion Resistance of Dissimilar Welded Joint between 304 Stainless Steel and Pure Copper

Abstract

Nowadays, welding of dissimilar metals has become significant. In this process, a number of parameters including but not limited to type of electrode, amount of current, preheating temperature, and welding rate, that are essential to be taken into account. For welding of dissimilar metals, various methods are exploited including shielded metal arc welding (SMAW) and gas tungsten arc welding (GTAW). The stimulus for studying welding of 304L stainless steel to pure copper originates from difficulties in joining copper parts of water-circulating molds to their steel part. In this study, the welding is performed on plates of steel and copper using SMAW, GTAW and combined SMAW+GTAW welding methods with EL-CuMn2, ENiCrMo-6 and ER70S-4 electrodes. In order to investigate the microstructure and corrosion resistance behavior of welds, the samples were characterized using microstructural study and polarization test. It was observed that among all four welding methods, only combined SMAW+GTAW welding process resulted in successful joint between 304L stainless steel and copper. Both obtained joints possess suitable microstructure and corrosion resistance.

Assessing crack susceptibility in blended copper-stainless steel compositions during laser directed energy deposition-based additive manufacturing

“…3 In recent times, there has been a growing interest among research groups in Cu-SS joints considering its wide potential applications in the above-mentioned sectors. [4][5][6][7] Metallurgical incompatibility and the diverse nature of Cu and SS due to the large difference in thermal expansion coefficient, and thermal conductivity leads to porosity and cracking during their welding. 4 In addition, the poor solubility of Cu and SS with each other causes unstable and complex melt-pool dynamics leading to solidification cracking and porosity during joining.…”

“…4 In addition, the poor solubility of Cu and SS with each other causes unstable and complex melt-pool dynamics leading to solidification cracking and porosity during joining. [4][5][6] Solidification cracking is the major source of cracking in the Cu-SS system due to a large solidification range and large difference in the thermal expansion coefficient. 8 Solidification cracking is primarily seen at the terminal stages of solidification due to the pulling action of solidifying grain on eutectic/liquid film.…”

The Joining of Copper to Stainless Steel by Solid-State Welding Processes: A Review

“…The diverse nature of both materials is dominant during fusion welding processes. However, considerable effort has been made to join copper to stainless steel via fusion welding processes [ 35 , 36 , 37 , 38 , 39 , 40 , 41 , 42 , 43 , 44 , 45 , 46 , 47 ]. Overall, it is safe to conclude that the metallurgy of copper to stainless steel joints must be the researcher’s focus when welding them with fusion welding processes.…”