In this paper,we consider the vector nonlinear boundary value problem:εy<sup>v</sup>=f(x,y,z,y′,ε),y(0)=A<sub>1</sub>,y(1)=B<sub>1</sub>εz<sup>v</sup>=g(x,y,z,z′,
Based on composite materials,the equivalent elastic-plastic constitutive equations ofmultiphase solid are researched.According to the suggested definition of.co