Influence of pressure on shrinkage porosity prediction
(1.黑龙江省哈尔滨市哈尔滨工业大学材料科学与工程学院2.School of Materials Science and Engineering, Harbin Institute of Technology, Harbin 150001, China)
Abstract: Most of the shrinkage porosity criteria only consider internal thermal conditions, but ignore external conditions, such as pressure. Therefore, to some castings with a relatively high molten metal hydrostatic pressure or atmosphere pressure, the shrinkage porosity prediction will not be accurate enough. In order to solve this problem, this work studies and improves a known shrinkage porosity criterion ‘Xue Criterion’. The pressure is introduced into the criterion function and a relationship between ‘Xue Criterion’ and the pressure is established. The modified ‘Xue Criterion’ function can be expressed as p0Gτ/τ. Compared with the previous experimental work, the prediction result from the new shrinkage criterion has a good agreement with the experimental result, and it is more accurate than the original ‘Xue Criterion’.
Key words: shrinkage porosity criterion； numerical simulation； defects prediction