Influence of Geometry and Process Variables on the Anisotropy Parameter K

Properly modelling the anisotropic dimensional change on sintering is a difficult task, given the large number of variables involved, which depend on material, process, and geometry. In previous works a preliminary analysis was performed, and an analytical model, based on experimental data, was proposed. This work investigates in depth the influence of geometry and process variables on the anisotropy parameter K, which allows estimating the entity of anisotropy. Axisymmetric iron parts were considered; the influence of the ratio between internal and external diameter was investigated. Special attention was paid to the dimensional changes in the compaction plane, those mainly affecting the design of the compaction tools, being different the influence of the process variables on the dimensional variation in the external and internal diameter. The influence of process parameters, specifically green density and sintering temperature, was also studied. A relationship between K and process variables is proposed.