초록 ▼

High-strength, fine-grain multi-phase substantially crystalline sintered ceramic bodies are produced by a process comprising the steps of cold pressing, followed by sintering at a high temperature, the temperature increase to maximum sintering temperature being accomplished by the use of a heating r

High-strength, fine-grain multi-phase substantially crystalline sintered ceramic bodies are produced by a process comprising the steps of cold pressing, followed by sintering at a high temperature, the temperature increase to maximum sintering temperature being accomplished by the use of a heating rate in excess of about 100°C./minute.

대표청구항 ▼

In the process for preparing multi-phase, substantially crystalline, sintered ceramic bodies in which a mixture of different powdered ceramic materials are consolidated under pressure to produce a pressed powder body of a preselected shape and volume, which unconfined pressed powder body is then hea

In the process for preparing multi-phase, substantially crystalline, sintered ceramic bodies in which a mixture of different powdered ceramic materials are consolidated under pressure to produce a pressed powder body of a preselected shape and volume, which unconfined pressed powder body is then heated in a furnace to a maximum sintering temperature and then permitted to cool, said mixture containing components that can chemically interact at elevated temperatures to inhibit densification or form phases undesirable for sintering, the improvement of employing a rapid heating rate in excess of about 100°C. per minute during at least that part of the heating cycle in which said maximum sintering temperature is reached and holding at said maximum: temperature for a period of time long enough to achieve uniform temperature distribution throughout said pressed powder body, said heating rate being rapid enough to densify said pressed powder body at a rate exceeding the rate of chemical reaction of said components and recovering a sintered body having a density of at least 94% theoretical and being free of any interconnected network of pores.