In the chemical composition design of GL DH32 steel plate, in order to make GL DH32 steel plate have good welding performance and better low-temperature impact toughness, it is necessary to reduce the carbon content in GL DH32 steel plate and control it to the lower limit. Because carbon is a strong solid capacity strengthening element, it can significantly increase the strength of GL DH32 steel plate, but it reduces toughness and plasticity, and significantly deteriorates the welding performance of GL DH32 steel plate.
Studies have shown that if the carbon content of GL DH32 steel plate is reduced to 0.04% ~ 0.07%, and the content of alloying elements is fine-tuned, plus controlled rolling, direct quenching (CRDQ) and tempering treatment, the preheating process before welding can be eliminated , The obtained 25mm thick plate can meet the mechanical performance requirements of GL DH32 steel plate.
