Evaluation of Welding Parameter's Effects on Corrosion Behavior of Bronze-Carbon Steel Dual-Layer Explosion Welded Joint at Salt Enviroment

Abstract

In the current investigation, corrosion behavior and microstructural variations of explosion-welded joint of bronze-carbon steel dual-layer plates were studied. The resultant curves of potentiodynamic's polarization tests demonstrated that the lowest corrosion rate was related to the sample with maximum explosive load thickness, and the highest corrosion speed was for the sample with minimum standoff distance. EIS test results of welded samples were indicative of creating a passive layer at the beginning of immersion process which showed that the polarization resistance has been reduced by increasing of explosive load thickness. So, the corrosion mechanism included two stages; at the beginning of immersion, for the samples with the lower thickness of explosive load, a passive layer would be created around the component due to higher concentration gradient and then, by removing of this layer, the galvanic couple determines the corrosion rate.

Investigating the effect of post weld heat treatment on corrosion properties of explosive bonded interface of AA5083/AA1050/SS 321 tubes

“…The corresponding electrical equivalent circuit for the samples in the solution is shown in figure 7(a) by presenting a schematic model of the potential distributions at the metal/solution interface (figure 7(b) and the dual layer resistance (figure 7(c). In the presence of inhibitors, the polarization resistance (R p ) consists of charge transition (R ct ), preventing layer resistance on the metal surface (R f ), all stored particles (inhibitory molecules, corrosion products, etc) at metal/solution interface (R a ) and the resistance of the diffusive layer (R d ) ( [12]. Dual layer capacity (C dl ) is calculated using below equation:…”

“…ZSimpWin 3.22 software was used to analyze the results of EIS. [12]. These compounds make it easier to diffuse aluminum and iron atoms during heat treatment in comparison to the formation of intermetallic compounds during explosive welding (figure 2(a)).…”

“…Increasing the temperature and operating time leads to the activation of the diffusion mechanism and the formation of intermetallic compounds at the interface. If intermetallic compounds are formed during explosive welding, it is easier to diffusion the iron and aluminum atoms during the heat treatment of samples [12].…”

“…(a) Potential distributions in the metal/solution interface (b) dual layer resistance (c), the proposed equivalent electrical circuit for a non-inhibitor solution[12].…”