IMPROVEMENTS INTRODUCED IN A MOLDING PROCEDURE WITH LOST FOAM, AND UNDER CONTROLLED PRESSURE, OF METAL PIECES.

摘要

IN THE PROCESS OF MOLDING WITH LOST FOAM AND A CONTROLLED PRESSURE OF METAL PIECES, THE PRESSURE IS INCREASED INITIALLY AT A SPEED COMPRISING BETWEEN 0.003 AND 0.03 MPA / SEC DURING A PERIOD OF AT LEAST 5 SECONDS FROM THE BEGINNING OF THE PRINCIPLE OF PRESSURE AND THEN AT A SPEED HIGHER THAN THE FIRST PERIOD DURING A SECOND PERIOD AND THIS UNTIL THE MAXIMUM PRESSURE IS REACHED. THE PROCESS ALLOWS TO OBTAIN PARTS WHICH FORM CORRESPONDS TO THE MODEL AND WITHOUT POROSITIES.