Thin plates of 21% Cr ferritic stainless steel welded by pulsed gas tungsten arc welding at different pulse frequencies were investigated for the microstructure characteristics and hardness behavior.The welds containe...Thin plates of 21% Cr ferritic stainless steel welded by pulsed gas tungsten arc welding at different pulse frequencies were investigated for the microstructure characteristics and hardness behavior.The welds contained columnar grains in the outer part and fine equiaxed grains in the central region due to the pulsed process.展开更多
A series of ferrite/bainite(F/B) multi-phase steels containing different volume fractions of ferrite were obtained.The effect of soft phase(ferrite) content on the work-hardening behavior of the steel was studied by t...A series of ferrite/bainite(F/B) multi-phase steels containing different volume fractions of ferrite were obtained.The effect of soft phase(ferrite) content on the work-hardening behavior of the steel was studied by the finite element simulation with V-BCC model and the modified Crussard-Jaoul(C-J) analysis.It is shown that the multi-phase steels have an excellent anti-deformation ability,such as higher stress ratio(R t1.5 /R t0.5),higher uniform elongation and lower yield to tensile strength ratio.For the F/B multi-phase steels,increasing the proportion of ferrite would help to increase the uniform elongation.However,introducing much more fraction of ferrite would not be helpful to improve the stress ratio of multi-phase steel.The ferrite plastic strain constrained by bainite would be beneficial to increasing the work hardening rate.The optimum proportion of ferrite will result both higher stress ratio and uniform elongation in multi-phase steel.展开更多
A 9% Cr ferritic steel weld metal containing 1% Co, partially substituted for nickel, was prepared by submerged arc welding (SAW) processing. The microstructure and creep properties of the weld metal were investigated...A 9% Cr ferritic steel weld metal containing 1% Co, partially substituted for nickel, was prepared by submerged arc welding (SAW) processing. The microstructure and creep properties of the weld metal were investigated. The microstructure exhibited a fully tempered martensitic structure free of δ-ferrite. The creep properties of the obtained weld metal were inferior to those of the P92 base metal at 600 and 650 °C. The values of A and n for weld metal in the Norton power law constitution at 650 °C are 1.1×10?21 and 8.1, respectively.展开更多
文摘Thin plates of 21% Cr ferritic stainless steel welded by pulsed gas tungsten arc welding at different pulse frequencies were investigated for the microstructure characteristics and hardness behavior.The welds contained columnar grains in the outer part and fine equiaxed grains in the central region due to the pulsed process.
基金supported by the National Basic Research Program of China ("973" Program) (Grant No. 2010CB630801)
文摘A series of ferrite/bainite(F/B) multi-phase steels containing different volume fractions of ferrite were obtained.The effect of soft phase(ferrite) content on the work-hardening behavior of the steel was studied by the finite element simulation with V-BCC model and the modified Crussard-Jaoul(C-J) analysis.It is shown that the multi-phase steels have an excellent anti-deformation ability,such as higher stress ratio(R t1.5 /R t0.5),higher uniform elongation and lower yield to tensile strength ratio.For the F/B multi-phase steels,increasing the proportion of ferrite would help to increase the uniform elongation.However,introducing much more fraction of ferrite would not be helpful to improve the stress ratio of multi-phase steel.The ferrite plastic strain constrained by bainite would be beneficial to increasing the work hardening rate.The optimum proportion of ferrite will result both higher stress ratio and uniform elongation in multi-phase steel.
基金Project (No 51074113) supported by the National Natural ScienceFoundation of China
文摘A 9% Cr ferritic steel weld metal containing 1% Co, partially substituted for nickel, was prepared by submerged arc welding (SAW) processing. The microstructure and creep properties of the weld metal were investigated. The microstructure exhibited a fully tempered martensitic structure free of δ-ferrite. The creep properties of the obtained weld metal were inferior to those of the P92 base metal at 600 and 650 °C. The values of A and n for weld metal in the Norton power law constitution at 650 °C are 1.1×10?21 and 8.1, respectively.