Powder metallurgy process
Abstract
Abstract A METHOD OF PRODUCING AN IMPROVED TOOL STEEL HAVING A SUPERIOR ALLOY HOMOGENEITY WHICH COMPRISES THE STEPS OF PROVIDING A CHARGE OF IRREGUALRLY-SHAPED, FRACTURED, PREALLOYED TOOL STEEL POWDER OF A HOMOGENEOUS COMPOSITION, EXPOSING THE POWDERED PARTICLES TO A HYDROGEN REDUCING ATMOSPHERE TO REDUCE THE ODIXE CONTENT AND SLOWLY COOLING THE REDUCED POWDER PARTICLES TO AVOID IMPARTING AN OBJECTIONABLE DEGREE OF HARDNESS WHICH WOULD INTERFERE WITH SUBSEQUENT COLD PRESSING OF REDUCED POWDER PARTICLES, COLD PRESSING THE REDUCED POWDER PARTICLES TO A BILLET FORM HAVING A GREEN STRENGTH ADEQUATE TO MAINTAIN STRUCTURAL INTEGRITY UPON FURTHER HANDLING OF THE BILLET, AND SINTERING THE COLD PRESSED BILLET TO IMPART A THEORETICAL DENSITY OF AT LEAST 85% TO THE TOOL STEEL WITH THE SINTERING BEING CARRIED ON UNDER CONDITIONS TO MINIMIZE GRAIN GROWTH AND PHASE SEPARATION OF A DEGREE INSENSITIVE TO SUBSEQUENT PROCESSING.
Inventors
- 👤 R Matt
- 👤 A Levy
Bibliographic Details
Claims Analysis
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