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What about the welding process and post-weld heat treatment of pearlite steel?
Welding technology and post-weld heat treatment of pearlite steel;

When welding pearlite steel in dissimilar joints, in order to reduce the fusion ratio and the dilution of weld metal, large groove, low current, fast and multi-layer welding should be adopted. Due to the different expansion coefficients, the stress distribution can be changed by proper system design and joint arrangement, and long welds should be welded in sections.

The choice of heat treatment process for welded joints of dissimilar austenitic steels depends on the brand of steel, the shape of components and working conditions. When welding general heat-resistant steel that does not need to eliminate welding stress and works at medium temperature, post-weld heat treatment can be omitted. For the parts that require to eliminate welding stress in manufacturing requirements and service conditions, it is only necessary to stabilize them at 800 ~ 850℃. For parts working at high temperature, the welded parts shall be austenitized at1100 ~1150℃. However, if intergranular corrosion resistance is required, the austenitizing temperature should not exceed 1050℃. If dispersion strengthened austenitic steel is used in welded joints, heat treatment must be carried out after welding to restore the properties of the near-seam zone. At this time, the selection of heat treatment process is usually based on the requirements of dispersion strengthened steel.

Covered electrode, preheating and post-weld heat treatment of pearlite steel must be properly preheated if one of the dissimilar steels to be welded has a strong tendency of hardening ability. The dissimilar joints of pearlite steel and austenitic steel with high hardening tendency need post-weld heat treatment to prevent microstructure hardening, reduce welding residual stress and prevent cold cracks. Because the above-mentioned welded joints produce embrittlement and diffusion layer in the fusion zone, especially when welding rigid members with large thickness, the weldment may be brittle in the fusion zone during tempering treatment or later use. Therefore, high-nickel covered electrode can be used to build-up welding on the surface of pearlite steel groove before welding. Because of the different expansion coefficients of pearlite steel and austenitic steel, great residual stress will be produced at the joint after welding. Through proper system design and joint arrangement, the external load acting on the joint can be reduced, and the transition layer can be increased if necessary.