It is pointed out that crystals are discrete but not continuous materials. Hence the rotation R in decomposition F=RU and spin W in F -1 are not correct. Errors will arise in plastic deformation rate ...It is pointed out that crystals are discrete but not continuous materials. Hence the rotation R in decomposition F=RU and spin W in F -1 are not correct. Errors will arise in plastic deformation rate if it is directly expressed with amounts of velocity of slips in glide systems such as vn. The geometrical figure of crystal lattices does not change after slips and based on this idea a simple way in mechanics of continuous media to get the plastic deformations rate induced by slips is proposed. Constitutive equations are recommended.展开更多
Based on Illiushin's two hypotheses, a new plastic constitutive equation of integral type is proposed. The deviatoric stress induced by a strain path consists of two parts which vary according to different laws. C...Based on Illiushin's two hypotheses, a new plastic constitutive equation of integral type is proposed. The deviatoric stress induced by a strain path consists of two parts which vary according to different laws. Comparison of theoretical calculation with recent experiments is satisfactory. The present theory is not an endochronic theory.展开更多
The perturbation method and finite strip method are combined to solve the large deflection bending problems of rectangular plates. Perturbation method is used to reduce the nonlinear differential equations into a seri...The perturbation method and finite strip method are combined to solve the large deflection bending problems of rectangular plates. Perturbation method is used to reduce the nonlinear differential equations into a series of linear differential equations. The finite strip method is then employed to tackle these linear equations. Some calculation examples are compared with those got by other methods.展开更多
文摘It is pointed out that crystals are discrete but not continuous materials. Hence the rotation R in decomposition F=RU and spin W in F -1 are not correct. Errors will arise in plastic deformation rate if it is directly expressed with amounts of velocity of slips in glide systems such as vn. The geometrical figure of crystal lattices does not change after slips and based on this idea a simple way in mechanics of continuous media to get the plastic deformations rate induced by slips is proposed. Constitutive equations are recommended.
文摘Based on Illiushin's two hypotheses, a new plastic constitutive equation of integral type is proposed. The deviatoric stress induced by a strain path consists of two parts which vary according to different laws. Comparison of theoretical calculation with recent experiments is satisfactory. The present theory is not an endochronic theory.
文摘The perturbation method and finite strip method are combined to solve the large deflection bending problems of rectangular plates. Perturbation method is used to reduce the nonlinear differential equations into a series of linear differential equations. The finite strip method is then employed to tackle these linear equations. Some calculation examples are compared with those got by other methods.