Grain growth pressure sintering

There is yet another way to suppress excessive grain growth and thus to attain high relative densities. It is provided by hot pressing (sintering under pressure), which is used particularly in the manufacture of sintered carbides and nitrides. Even at high temperatures, these substances show low atom mobility so that spontaneous... 

Grain-growth studies have also been carried out under 1 atm of nitrogen pressure [25]. The results were found to be different from those studies performed at 10 atm. The time exponent n for both directions was equal to 3. This will result in an equation in which the exponent of the time term is equal to one, and the aspect ratio is time independent during sintering. 

K. R. Lai and T. Y. Tien, Kinetics of j3-Si3N4 grain growth in silicon nitride ceramics sintered under high nitrogen pressure. J. Am. Ceram. Soc. (in press). 

M. Mitomo, M. Tsutsumi, H. Tanaka, S. Uenosono and F. Saito, Grain Growth During Gas-Pressure Sintering of P-Silicon Nitride , J. Am. Ceram. Soc., 73, 1990, 2441-45. 

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