3 Cooling of molten metal Temperature time curve structure on solidification

3 cooling of molten metal temperature time curve

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3. Cooling of molten metal: Temperature time curve structure on solidification. 4. Factors affecting grain size & structure: Rate of cooling nucleating agents cold working stress relief anneal recrystallisation grain growth. Model & die materials: 1. Required properties: Strong produce fine details little dimensional changes on setting compatible with impression material color conrtrast cheap & easy use. 2. Gypsum products: Plaster of paris dental stone improved stone. 3. Methods of production: Plaster of paris obtained by prolonged heating of gypsum in open air at 120 ˚ c. Dental stone obtained by heating gypsum at 120 ˚ c-130 ˚ c in an autoclave under steam pressure. Improved stone obtained by heating gypsum in poiling 30% solution of Ca Cl 2 or Mg Cl 2. PDF created with pdfFactory Pro trial version
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