The propagation and accumulation of dimensional shrinkage in investment casting

摘要

The injection of wax pattern and the solidification of the metal are both essential procedures and having the major influences on the final dimensions. However, the main casting process steps and casting geometry affecting the dimensional shrinkage wasn't quantitatively studied. In this study, dimensional shrinkage has been investigated with a ring to ring part. The displacement of wax pattern and its corresponding casting is measured by 3D laser scanner. An unconstrained dimension of diameter is, on average, contract with 0.849% for wax pattern and 2.559% for casting. A direct linear relationship of dimensions in outer ring is established between the wax patterns with its castings. The statistical quantitative results show that the accuracy of dimensions in outer ring is dominantly influenced by metal thermal contraction in casting process.