Stress Corrosion Cracking Threshold for Dissimilar Capacitive Discharge Welding Joint with Varied Surface Geometry

Abstract

Stress corrosion cracking (SCC) is known as a major factor that should be considered in the assessment of welding joint structure integrity. Despite the promising and wide application of dissimilar metal joints, the currently available SCC mitigation technique of dissimilar metal joints is not adequate. The challenge is to obtain a good joint while different melting points exist. This article reports a novel SCC mitigation method on a brass–steel dissimilar metal joint by modifying the geometry of the surface. It is evidenced that the sharpened steel (α1 specimen) significantly improves the SCC resilience of the joint. The evaluation of SEM/EDS photos reveals that the α1 geometry induces a smaller pore area around brass–steel micro-joint interfaces which in turn produces stronger joints.

Optimum power for ER-70S-2 and SS400 dissimilar CDW joint

“…A welding parameter optimization (power) study is carried out to determine the joint's longest time to stand under an SCC load. This research is a continuation of previous published papers [25,26] which discussed SCC and/or CDW respectively. The [25] is the first paper of us which discussed the SCC and the [26] is the SCC consideration when applied to the CDW joint.…”

“…This research is a continuation of previous published papers [25,26] which discussed SCC and/or CDW respectively. The [25] is the first paper of us which discussed the SCC and the [26] is the SCC consideration when applied to the CDW joint. The parameter varied in the [26] was surface preparation, while in this paper it is power.…”

“…Thus, two of the SCC's three components already exist in the weld joints, and when the weld joints are exposed to a corrosive environment, SCC can occur. The SCC behavior of fusion welding has been investigated using both experimental and numerical approaches via quantitative and qualitative methods [11][12][13][14][15][16][17]. Kim et al [11] studied the effect of residual stress on the SCC growth in GTAW joints.…”

“…When they exposed the specimen to vapors of 45% MgCl2 boiling at 155 °C, the time to failure of the welded joint was shorter than that of the parent metal. Darmadi et al [13] improved the resilience to SCC loads of the Capacitive Discharge Welding Joint by varying the surface shape of the welded tips. The welded metals were steel and brass.…”

“…The [25] is the first paper of us which discussed the SCC and the [26] is the SCC consideration when applied to the CDW joint. The parameter varied in the [26] was surface preparation, while in this paper it is power. Based on the previous report [22], the advantage of using CDW is better quality when applied to dissimilar metals, and in this report the ER-70S-2 and SS400 are used.…”