The surface layer of sintered compacts using the pulse electric current sintering method is heated at higher temperature than the inside of the compacts. As the result, the density of the surface layer is higher than that of inside part, there is a possibility of canning-less HIP treatment.
To promote the sintering at surface layer, the sintered compacts were prepared at various initial currents using the pulse electric current sintering method. But the porosity difference in the position of the various sintered compacts made with copper powder is little. It is difficult to make the closed pores at the surface layer of the sintered compacts. The copper sintered compacts treated by canning-less HIP treatment at 100 MPa and 0.1 MPa did not show the difference in tensile strength, density and morphology at fracture surface. There was no possibility of canning-less HIP treatment techniques of the sintered compacts using the pulse electric current sintering method.