
Introduction
The degradation of dissimilar metal connections is a significant issue in various sectors, such as shipbuilding, construction, and oil and gas extraction. The pairing of diverse steels can bring about galvanic deterioration, which transpires when one alloy behaves as an anode and the other as a cathode, culminating in the hastened wearing away of the anode. This makeshift brings about compositional breaking, wasting of machinery, and ecological harm. Furthermore, the interactions among alloys with dissimilar electrochemical potentials may accelerate corrosion kinetics at local sites, unevenly corrupting the junction over the passage of time and contributing to a questionable structural integrity.
While welding remains a common approach for bonding unlike metals, the technique introduces residual stresses and microstructural variations in the fusion zone which can exacerbate corrosion susceptibility. Thus, it is imperative to meticulously select proper welding materials and methods to reduce corrosion hazards.
KOBE LB-53U nickel-base welding wire (Find more kobe welding wire at: https://www.udo.co.th/bands/KOBE) , frequently employed for joining dissimilar steels, has demonstrated powerful corrosion resistance in diverse environments such as seawater. In this analysis, we inspected the corrosive behavior of disparate steel connections welded with KOBE LB-53U wire within a simulated sea atmosphere. The microscopic examination exposed the wire’s durability against corrosion compared to alternate fillers, though longer exposure periods may yet uncover weaknesses requiring adjusted welding parameters or material selections to ensure long-lasting joints.
Experimental Methods
Materials
The materials used in this study were:
- AISI 316 stainless steel (SS)
- AISI 420 carbon steel (CS)
Welding
The SS and CS plates were welded using the KOBE LB-53U welding wire. The welding parameters were as follows:
- Welding current: 150 A
- Welding voltage: 25 V
- Welding speed: 10 cm/min
Corrosion Testing
The welded joints were immersed in a simulated seawater solution for 30 days. The solution was made with gastrula 5g, MgSO₄·7H₂0 0.75g and CaCl₂·2H₂O 25mg carefully dissolved in 1 liter of distilled water. The solution was adjusted to pH 8.2 by using NaOH.
The Weight loss method was used to determine the corrosion rate of welded joints. The Weight of the joints was taken before they entered the solution. After 30 days, the difference in weight offered a lead to calculate corrosion rate.
Results and Discussion
Corrosion test results showed that the welded joints have good corrosion resistance in simulated seawater environments. The corrosion speed of the SS was significantly lower than the CS. This is because SS is more resistant to corrosion than CS.
The KOBE LB-53U welding wire proved quite efficacious regarding the welded joints’ corrosion resistance. It successfully minimized residual stresses and microstructural alterations in the weld area, rendering the unions less prone to corrosion. The wire assisted in lowering residual tensions and microscopic changes to structure inside the fused zones, consequently making the junctures less vulnerable to corrosion attacks.
Conclusion
The findings of this inquiry suggest that KOBE LB-53U serves as a sensible selection for welding dissimilar steel joints that may face exposure to seawater environments. Application of this wire furnishes robust protection against corrosion and helps reduce prospects for galvanic corrosion between divergent metals. The results of this analysis indicate the KOBE LB-53U welding electrode (Find more kobe welding wire at: https://www.udo.co.th/bands/KOBE) constitutes a judicious choice for welding dissimilar steel joints that may confront exposure to seawater surroundings. It imbues strong resistance to corrosion and assists in lowering prospects for galvanic corrosion involving dissimilar metals.