After the substructure for a porcelain-bonded-to-metal crown is cast in metal,why is it heated at high temperature?

Name: After the substructure for a porcelain-bonded-to-metal crown is cast in metal,why is it heated at high temperature?
Brand: Quizplus
Rating: 4.8 (61 reviews)

Question

Quizplus · Accepted Answer

After the substructure for a porcelain-bonded-to-metal crown is cast in metal,it is heated at high temperature to form oxides on the surface of the metal.This process is called degassing,although oxidizing would be a more accurate term.

After the Substructure for a Porcelain-Bonded-To-Metal Crown Is Cast in Metal,why