Casting Solidification Feed-Path Computation and Industrial Application

摘要

Metal casting solidification is accompanied by volumetric shrinkage, compensated by microscopic flow of liquid from adjacent hotter regions along the direction of the highest temperature gradients, referred to as feed-paths. The feed-paths converge to local hot spots, which lead to shrinkage porosity defects. Ideally, hot spots should be inside feeders, implying shrinkage defect-free castings. Visualization of 3D feed-paths facilitates analyzing and optimizing the design of feeders to obtain the desired quality at the highest possible yield. We present our work in this area, spanning the last two decades starting from Modulus Vector Method in 2D (1988) and 3D (1996), Vector Element Method (2006), and Gradient Vector Method (2012). The melt is assumed to be stationary, and convection effects are neglected. It is mainly applicable to thick-walled castings poured under gravity in sand molds. The feed-path computation has been incorporated in an integrated casting design software, and validated on several industrial case studies.