An analysis of the can effect in an isostatic pressing of copper powder

Anisotropic shrinkage during hip of encapsulated powder

“…On one hand, the capsule provides shielding of the gas pressure in the HIP-unit; on the other hand it also hinders pressure transmission to the powder because of its rigidity as described by Hirayama et al (2011). Result in Xu and McMeeking (1992) and Sanchez et al (2004) showed that the pressure applied on powder can be up to 20 MPa lower than the gas pressure applied on the capsule surface and stress stage inside the powder contains not only hydrostatic but also deviatoric stress. Result of and (Shiokawa et al, 2011) which did not give details of initial density distribution and temperature condition, found that isotropic shrinkage occurs when the capsule material is thin and uniform.…”

“…The hot isostatically pressed tubes and long cylinder capsules bent toward the side which has lower relative density (RD). Furthermore, not only the initial powder distribution, but also capsule shape , size (Samarov et al, 2014) and thickness (Xu and McMeeking, 1992) and the process parameters pressure and temperature (Li and Ashby, 1987) will contribute to the final shape of hot isostatically pressed components which are quantitatively mentioned by Trasorras et al (1994) and Li and Easterling (1992). So far, the temperature in the HIP vessel is assumed to be homogeneous and the temperature applied to a FEM model as initial condition is usually assumed to be homogeneous around the surfaces of the capsule.…”

Computer modelling and tooling design for near net shaped components using hot isostatic pressing

“…• It is worth noting that the shielding effect of the container is not negligible since the stresses in the powder are significantly smaller than the applied HIP pressure. Xu and McMeeking [21], have shown in their study that the compressive stresses in the powder are about 20 MPa less than the pressure applied to the exterior of the capsule and the powder is not in a state of hydrostatic pressure. A complete calculating procedure is necessary for the refinement of the model.…”

“…These material properties are used for the calculation of powder densification coefficients f 1 (ρ)and f 2 (ρ) according to Eqs. (21) and (22) and their values are plotted in Fig. 5.…”

Producing large P/M near-net shapes using hot isostatic pressing

“…The materials conventionally used in canister fabrication have sufficient strength at elevated temperature to provide structural reinforcement to corners of a powder-filled can. 4 As a result, the HIPing of a filled canister made of conventional materials will result in the distortion of surfaces adjacent to the corners. An improved understanding of the deformation of can materials during processing has helped to minimize this problem.…”