Power metallurgy hot isostatic pressing (PM-HIP) is a manufacturing technique capable of producing net shape or near-net shape components with complicated geometries from materials that are difficult to melt and cast, mechanically deform or weld. However, the process and soundness of the outcome are extremely sensitive to the geometric design of the capsule (also known as the die or can) that is used in the process. The capsule design for each new component involves several trial–error iterations to achieve the desired geometry and shape of the component. For each iteration, costly HIP experiments need to be conducted and new capsules need be manufactured with small modifications. In this study, a robust finite element analysis (FEA) model of the HIP process is developed, then wrapped in a multi-objective genetic algorithm (MOGA) optimization framework to obtain the optimal pre-HIP capsule design, which yields the desired post-HIP component geometry in one HIP run. The FEA-based optimization algorithm is validated by HIP experiments, showing excellent agreement between the experiment and the model.

Power Metallurgy Hot Isostatic Pressing (PM-HIP) is a manufacturing process, capable of producing net shape or near net shape components with complicated geometries from materials that are often difficult to cast and/or deform. However, the post-HIP quality and requirement of any additional process, such as machining, depends on the design and geometric complexity of the capsule. First of a kind geometry often requires several iterations of prototype builds. Considering the cost and long durations of HIP cycles, usage of computer models in order to predict parameters for an optimal capsule design of a PM-HIP process which produces a sound product in the first trial is extremely valuable. In this study, the pre-consolidation capsule filling process is simulated by Discrete Element Method (DEM) to capture the initial relative density. Finite element analysis (FEA) modeling of HIP, which includes a combined constitutive model based on compressive and consolidative mechanical behavior of powder uses the DEM results as input. Accuracy of the simulation tool is confirmed by comparing against a corresponding physical PM capsule fabrication and HIP experiment with pre- and post-HIP 3D scanning. The result shows that consolidation occurs as the model predicts, with negligible deviations on sharp edges.