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(1) Selecting weld metal with a strength level equivalent to that of the base metal, based on the different strength grades of the steel, is the basic principle for choosing welding materials for such steels. Of course, at the same time, factors such as the operating conditions of the product, its structure, and the thickness of the sheet must also be taken into account, in order to comprehensively consider the toughness and plasticity of the weld metal as well as the crack resistance of the welded joint. As long as the weld strength is at least equal to, or slightly higher than, the lower limit of the standard tensile strength of the base material, that is sufficient. If the weld metal strength of the selected welding material is too high, it will result in reduced toughness, plasticity, and crack resistance of the joint, and its bending performance will be unlikely to meet the required standards. (2) Since these steels all exhibit varying degrees of susceptibility to cold cracking, it is very important to strictly control the hydrogen content in the welding materials under the principle of equal strength; therefore, low-hydrogen welding materials should be preferred whenever possible. This is especially true when welding high-strength low-alloy quenched and tempered steels; in such cases, ultra-low hydrogen welding materials must be selected, and their storage and use must be strictly controlled. (3) Consider the influence of post-welding processing techniques. For welded parts that require heat treatment or hot rolling (hot bending) after welding, the effect of high-temperature treatment on the mechanical properties of the weld metal must be taken into account; it is necessary to ensure that the weld metal retains the required strength, ductility, and toughness after heat treatment. For example, in the submerged arc welding of 16MnR steel, which is commonly used for pressure vessels, H10Mn2 wire combined with HJ431 flux is generally sufficient. However, for the joint welds of head gussets that require stamping at normalizing temperature after welding, the grade of welding material used should be elevated by one level; using H08MnMo wire together with HJ431 flux can compensate for the loss in strength.