Numerical Study of Near-Net-Shape Forming under Encapsulation Technologies and HIP Cladding

摘要

Today, diffusion bonding remains a common application for Hot Isostatic Pressing (HIP) of high-performance components. Encapsulation technologies and HIP enable a premium material in powder form to clad a solid substrate and densify to produce a high-performance surface for corrosion- or wear protection. The production of near-net-shape components with precise tolerance saves cost of secondary machining or manual rework which are usually aimed for a better surface finish. In the frame of the AGRAL European project, this technology is developed for the manufacturing of inert electrodes to be used for the aluminium production. To achieve required coating thickness and shape by predicting the shrinkage of the capsule, numerical studies of the densification process of the coating layer are conducted by FEM simulation in ABAQUS. Metal-ceramic composite powder and nickel based alloy substrate are studied, whereas mild steel is used as the capsule material. The capsule shape is redesigned by an “Invert Optimization” tool based on parametric modelling, which is verified by several HIP cycles in experiments. Theoretical and experimental results show high consistency.