A combined model to simulate the powder densification and shape changes during hot isostatic pressing
- Citation data:
Computer Methods in Applied Mechanics and Engineering, ISSN: 0045-7825, Vol: 315, Page: 302-315
- Publication Year:
- Engineering; Physics and Astronomy; Computer Science
Under high temperature and pressure during Hot Isostatic Pressing (HIP), various deformation and sinter mechanisms such as plastic yielding, power law creep, and diffusion occur. They contribute either simultaneously or consecutively to the densification process depending on temperature and pressure levels. Some published works have shown that neither the pure plastic model nor the pure viscoplastic model sufficiently models the densification process during HIP, therefore a combined model which includes both a time independent plasticity and a rate dependent plasticity (creep) should be used. An innovative aspect of this work in comparison with available models in literature is the accommodation for model inaccuracies in the initial creep stage. The densification model incorporates the initial creep mechanism which occurs for a short time with a higher rate as compared to the steady stage creep rate. In this study, a combined model which consists of the influence of plasticity, primary creep, and secondary creep mechanisms is used. The authors believe that this approach can improve the quality of “near-net-shape” simulation. Innovative Aspects : The proposed model is more robust and predicts the final shape of HIP-ed components better which will support the production of Selective Net Shape or Net Shape HIP components. The reported results are of importance for companies producing big and complex shaped components through powder-HIP.