A novel near-net process, gelcasting, was successfully used to prepare larger size 316L stainless steel parts with complex shape. In this study, the effects of process parameters on the viscosity of the slurry and the...A novel near-net process, gelcasting, was successfully used to prepare larger size 316L stainless steel parts with complex shape. In this study, the effects of process parameters on the viscosity of the slurry and the dry green strength were investigated. The results show that gas atomization （GA） powder is more suitable for gelcasting compared with water atomization （WA） powder. The maximum solid loading is 55vo1% for ball-milled slurry with GA powders. And the optimum amounts of monomers （acrylamide （AM）＋methylenebisacrylamide （MBAM）; the mass ratio, 30：1） and initiator in the AM system are 1.8% （based on the weight of metal powder） and 0.8%-1.4% （based on the weight of monomers）, respectively, at which, the maximum green strength obtained is 33.7 MPa. The mechanical properties of the sintered specimen are as follows： ultimate tensile strength, 493 MPa; yield strength, 162 MPa; and HRB, 72.展开更多
Accurate boundary conditions of composite material plates with different holes are founded to settle boundary condition problems of complex holes by conformal mapping method upon the nonhomogeneous anisotropic elastic...Accurate boundary conditions of composite material plates with different holes are founded to settle boundary condition problems of complex holes by conformal mapping method upon the nonhomogeneous anisotropic elastic and complex function theory. And then the two stress functions required were founded on Cauchy integral by boundary conditions. The final stress distributions of opening structure and the analytical solution on composite material plate with rectangle hole and wing manholes were achieved. The influences on hole-edge stress concentration factors are discussed under different loads and fiber direction cases, and then contrast calculates are carried through FEM.展开更多
文摘A novel near-net process, gelcasting, was successfully used to prepare larger size 316L stainless steel parts with complex shape. In this study, the effects of process parameters on the viscosity of the slurry and the dry green strength were investigated. The results show that gas atomization （GA） powder is more suitable for gelcasting compared with water atomization （WA） powder. The maximum solid loading is 55vo1% for ball-milled slurry with GA powders. And the optimum amounts of monomers （acrylamide （AM）＋methylenebisacrylamide （MBAM）; the mass ratio, 30：1） and initiator in the AM system are 1.8% （based on the weight of metal powder） and 0.8%-1.4% （based on the weight of monomers）, respectively, at which, the maximum green strength obtained is 33.7 MPa. The mechanical properties of the sintered specimen are as follows： ultimate tensile strength, 493 MPa; yield strength, 162 MPa; and HRB, 72.
基金This project is supported by National Natural Science Foundation of China(No.50175031).
文摘Accurate boundary conditions of composite material plates with different holes are founded to settle boundary condition problems of complex holes by conformal mapping method upon the nonhomogeneous anisotropic elastic and complex function theory. And then the two stress functions required were founded on Cauchy integral by boundary conditions. The final stress distributions of opening structure and the analytical solution on composite material plate with rectangle hole and wing manholes were achieved. The influences on hole-edge stress concentration factors are discussed under different loads and fiber direction cases, and then contrast calculates are carried through FEM.
