Research on Deposited Metal Alloy Series of High-Strength SMAW Electrode

Deposited metal of high-strength SMAW electrode of MnNiMo and 7%NiMo alloy series were investigated.The results indicate that high-strength weld metal from MnNiCrMo series electrodes were obtained on condition of 0.05%-0.07% carbon content with yield strength exceeding 900MPa,toughness A_kv-50℃ 40-60J and yield ratio 0.93-0.98.The strength was stable.High-strength weld metal from 7%NiMo series electrodes were obtained at the condition of carbon content below 0.05% with yield strength exceeding 900MPa,toughness A_kv-50℃ 50-80J and yield ratio 0.92~0.94,while the plasticity of the weld metal was poor.The weld metallurgical microstructure and residual austenite content were analyzed,which provided necessary foundation for optimizing deposited metal alloy series of high-strength SMAW electrode.