High-strength Weldox700E steel has been increasingly applied to dynamic environment because of its high strength and good toughness. The plastic deformation behaviors of Weldox700E steel at strain rates ranging from 1...High-strength Weldox700E steel has been increasingly applied to dynamic environment because of its high strength and good toughness. The plastic deformation behaviors of Weldox700E steel at strain rates ranging from 10^-4 to 6200 s^-1 are investigated by the quasistatic and dynamic uniaxial compression tests. The Weldox700E steel exhibits rate-related plastic behavior, work hardening and thermal softening behaviors. Due to the nonlinear strain rate effect of the material and the adiabatic temperature rise caused by high-speed impact compression, the properties of material are greatly affected. By improving the strain rate enhancement term and temperature term in the Johnson-Cook constitutive model, a new constitutive model was proposed to describe the dynamic mechanical behavior of Weldox700E steel. This constitutive equation was implemented into the finite element software, ABAQUS, via an explicit user material subroutine utilizing the stress update algorithm. The simulation results at different strain rates were in good agreement with the experimental data, verifying the validity of the constitutive model.展开更多
The paper deals with investigations concerning the structure and state of dispersive precipitations of the phases consolidating in the high-strength steel Weldox 1300 after its high temperature thermomechanical treatm...The paper deals with investigations concerning the structure and state of dispersive precipitations of the phases consolidating in the high-strength steel Weldox 1300 after its high temperature thermomechanical treatment.Making use of transmission technique of electron microscopy (TEM) mainly the microstructure and morphology of martensite was analysed,as well as the state of dispersive precipitations of carbides and nitrides resulting from microadditives of such alloys as Nb,V,Ti or B,introduced into the steel.Observations revealed both a fine lathed and twin structure of the matrix of martensite in the investigated steel.By means of the method of electron diffraction particles of secondary strengthening phases of the M(C,N) type of a nanocrystalline size could be identified,and also non-metallic oxide inclusions,affecting the mechanism of strengthening of the investigated steel.展开更多
文摘High-strength Weldox700E steel has been increasingly applied to dynamic environment because of its high strength and good toughness. The plastic deformation behaviors of Weldox700E steel at strain rates ranging from 10^-4 to 6200 s^-1 are investigated by the quasistatic and dynamic uniaxial compression tests. The Weldox700E steel exhibits rate-related plastic behavior, work hardening and thermal softening behaviors. Due to the nonlinear strain rate effect of the material and the adiabatic temperature rise caused by high-speed impact compression, the properties of material are greatly affected. By improving the strain rate enhancement term and temperature term in the Johnson-Cook constitutive model, a new constitutive model was proposed to describe the dynamic mechanical behavior of Weldox700E steel. This constitutive equation was implemented into the finite element software, ABAQUS, via an explicit user material subroutine utilizing the stress update algorithm. The simulation results at different strain rates were in good agreement with the experimental data, verifying the validity of the constitutive model.
文摘The paper deals with investigations concerning the structure and state of dispersive precipitations of the phases consolidating in the high-strength steel Weldox 1300 after its high temperature thermomechanical treatment.Making use of transmission technique of electron microscopy (TEM) mainly the microstructure and morphology of martensite was analysed,as well as the state of dispersive precipitations of carbides and nitrides resulting from microadditives of such alloys as Nb,V,Ti or B,introduced into the steel.Observations revealed both a fine lathed and twin structure of the matrix of martensite in the investigated steel.By means of the method of electron diffraction particles of secondary strengthening phases of the M(C,N) type of a nanocrystalline size could be identified,and also non-metallic oxide inclusions,affecting the mechanism of strengthening of the investigated steel.
