주임선의 형태와 용융기전이 Nickel-Chromium 합금의 다공성에 미치는 영향 = The Influence on Casting Porosity of Nickel-Chromium Alloy According to Sprue Design and Heat Source

다국어 초록 (Multilingual Abstract)

Using 3 sort of sprue design, 2 sort of heat source and nickel-chromium alloy, sample of total 36 were constructed, The result of experimental was researched on casting porosity on metal alloy according to the sort of sprue design and that heat source.
The results were as follows :
1. The largest volume of casting porosity was direct sprue (closed type), the nest was runner bur type and were type.
2. The influence on casting porosity of sprue design was greater than heat source.
3. When the type of heat source were used oxygen-acetylene and induction method, the volume of casting porosity was little difference.