Reduction of Porosity in Investment-Casted Pink Silver: A Case Study of A Jewelry Company
Keywords:Investment Casting; Porosity; Pink Silver; Design of Experiments
Shrinkage porosity was a major defect found up to 56% in an investment-casted pink silver of the case study company. This research was aimed to reduce the defect by using experimental designs with full factorial design 3k strategy to study the influential casting factors and to find the optimal casting conditions. The casting factors included flask temperature and casting temperature while the response variable was the percentage of porosity area. Results showed that using the flask temperature at 600 oC with the casting temperature at 1030 oC or using the flask temperature at 480 oC with the casting temperature at 1060 oC provided the minimum percentage of shrinkage porosities. These optimal casting conditions reduced the percentage of defects by 29.5% on average.
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