Super tough monolithic silicon nitride

Details Super tough monolithic silicon nitride Super tough monolithic silicon nitride

1991-09-17

1992-03-31

Dixon, Jr., William R.

Compositions: ceramic

Ceramic compositions

Refractory

501 98, C04B 3558

Patent

active

051008475

ABSTRACT:
A monolithic silicon nitride ceramic is densified at temperatures lower than 2000.degree. C. and heat treated at temperatures greater than 2000.degree. C. in the presence of at least 6.5 w % of multi-component sintering aids. This monolithic silicon nitride has a highly acicular microstructure Chevron Notch fracture toughness greater than 9 MPa.multidot.m.sup.1/2, R-curve behavior, high Weibull modulus, excellent damage tolerance, high thermal conductivity, and other desirable properties.

REFERENCES:
patent: 4225356 (1980-09-01), Prochazka et al.
patent: 4543345 (1985-09-01), Wei
patent: 4609633 (1986-09-01), Fukuhara et al.
patent: 4692420 (1987-09-01), Oda et al.
patent: 4879080 (1989-11-01), Hsieh
patent: 4904624 (1990-02-01), Yeckley
patent: 4919689 (1990-04-01), Pyzik et al.
Iskoe & Lange, "Development of Microstructure & Mechanical Properties . . . ", Cer. Microstructures '76 (ed. by Fulrath & Pask, Westview Press) 669-678 (1977).
F. F. Lange, "Fracture Toughness of Si.sub.3 N.sub.4 as a Function of the . . . ", J. Am. Cer. Soc., vol. 62, 428-430 (1979).
F. F. Lange, "Fabrication and Properties of Dense Polyphase Silicon Nitride", Am. Ceram. Soc. Bull., vol. 62, 1369-1374 (1983).
Tani et al., "Gas-Pressure Sintering of Si.sub.3 N.sub.4 with Concurrent Addition . . . ", American Ceram. Soc. Bull., vol. 65, 1311-1315 (1986).
Shalek et al., "Hot Pressed SiC Whisker/Si.sub.3 N.sub.4 Matrix Composites", American Ceram. Soc. Bull., vol. 65, 351-356 (1986).
Salem & Shannon, "Fracture Toughness of Si.sub.3 N.sub.4 Measured with short Bar . . . ", J. of Mat. Science, 22, 321-324 (1987).
Jenkins et al., "A 3-D Finite Element Analysis of a Chevron-Notched . . . ", Int. J. of Fract. 34, 281-295 (1987).
"Engineering Property Data on Selected Ceramics, vol. 1, Nitrides", Battelle Columbus Lab., Columbus, Ohio, p. 5.3.3-3 (1976).
G. Ziegler, "Effect of Phase Composition and Microstructure on the . . . ", J. Mat. Sci., 16, 495-503 (1981).

Affiliated with

Also associated with

Rating

Super tough monolithic silicon nitride does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Super tough monolithic silicon nitride, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Super tough monolithic silicon nitride will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-2259137