(under subclass 459) Process including exhausting air or other gases from the immediate contiguous environment of a casting material to a negative pressure differential with respect to the surrounding ambient environment of the casting material.
SEE OR SEARCH THIS CLASS, SUBCLASS:
7.1+, for processes of applying a vacuum in a mold-forming operation.
SEE OR SEARCH CLASS
75, Specialized Metallurgical Processes, Compositions for Use Therein, Consolidated Metal Powder Compositions, and Loose Metal Particulate Mixtures, appropriate subclasses for vacuum treatment of metals.
264, Plastic and Nonmetallic Article Shaping or Treating: Processes,
500+, for processes of vacuum forming plastic materials; and subclasses 101+ for processes of vacuum treating work.
