초록 ▼

Improved silicon carbide composites made by an infiltration process feature a metal phase in addition to any residual silicon phase. Not only are properties such as mechanical toughness improved, but the infiltrant can be so engineered as to have much diminished amounts of expansion upon solidificat

Improved silicon carbide composites made by an infiltration process feature a metal phase in addition to any residual silicon phase. Not only are properties such as mechanical toughness improved, but the infiltrant can be so engineered as to have much diminished amounts of expansion upon solidification, thereby enhancing net-shape-making capabilities. Further, multi-component infiltrant materials may have a lower liquidus temperature than pure silicon, thereby providing the practitioner greater control over the infiltration process. In particular, the infiltration may be conducted at the lower temperatures, where low-cost but effective bedding or barrier materials can terminate the infiltration process once the infiltrant has migrated through the permeable mass up to the boundary between the mass and the bedding material.

대표청구항 ▼

Improved silicon carbide composites made by an infiltration process feature a metal phase in addition to any residual silicon phase. Not only are properties such as mechanical toughness improved, but the infiltrant can be so engineered as to have much diminished amounts of expansion upon solidificat

Improved silicon carbide composites made by an infiltration process feature a metal phase in addition to any residual silicon phase. Not only are properties such as mechanical toughness improved, but the infiltrant can be so engineered as to have much diminished amounts of expansion upon solidification, thereby enhancing net-shape-making capabilities. Further, multi-component infiltrant materials may have a lower liquidus temperature than pure silicon, thereby providing the practitioner greater control over the infiltration process. In particular, the infiltration may be conducted at the lower temperatures, where low-cost but effective bedding or barrier materials can terminate the infiltration process once the infiltrant has migrated through the permeable mass up to the boundary between the mass and the bedding material. the determined amount of solvent to the viscosity control tank to adjust the resin density of the waste resist; removing dust from the waste resist having the adjusted resin density, to obtain the refreshed waste resist; and supplying the refreshed waste resist for resist coating. 9. A method of resist coating according to claim 8, wherein the viscometer is an ultrasonic viscometer. 10. A method of resist coating according to claim 8, wherein the relationship between the electric current value and resin density is Y=ALnX+B, wherein Ln is a natural logarithm, A and B are coefficients determined by compositions of the waste resist and the solvent, X is the electric current value, and Y is the resin density. 11. A method of resist coating according to claim 10, wherein the coefficients A and B are based on expressions as follows: A=CT+D, and B=ET+F, wherein C, D, E and F are coefficients determined by compositions of the waste resist and the solvent, and T is a temperature of the waste resist. 12. A method of resist coating according to claim 8, wherein said calculating a resin density is based on a following expression: Y=(CT+D) LnX+ET+F, wherein Ln is a natural logarithm, C, D, E and F are coefficients determined by compositions of the waste resist and the solvent, T is a temperature of the waste resist, X is the electric current value, and Y is the resin density. 13. A method of resist coating according to claim 8, further comprising supplying gaseous nitrogen to the viscosity control tank. 14. A method of resist coating comprising: providing edge rinse resist liquid or back rinse resist liquid from a resist coating process as wasted resist; collecting the wasted resist in a tank; measuring a viscosity of the wasted resist in the tank by a viscometer so as to obtain an electric current value; determining a relationship between the electric current value and resin density of the wasted resist; calculating a resin density of the wasted resist based on the relationship, the electric current value and a temperature of the wasted resist in the tank; determining an amount of solvent to add to the wasted resist based on a difference between the calculated resin density and a predetermined resin density; supplying the determined amount of solvent to the tank to adjust the resin density of the wasted resist; removing dust from the wasted resist having the adjusted resin density to obtain a refreshed resist; and supplying the refreshed resist for the resist coating process. 15. A method of resist coating according to claim 14, wherein the viscometer is an ultrasonic viscometer. 16. A method of resist coating according to claim 14, wherein the relationship between the electric current value and resin density is Y=ALnX+B, wherein Ln is a natural logarithm, A and B are coefficients determined by compositions of the wasted resist and the solvent, X is the electric current value, and Y is the resin density. 17. A method of resist coating according to claim 16, wherein the coefficients A and B are based on expressions as follows: A=CT+D, and B=ET+F, wherein C, D, E and F are coefficients determined by compositions of the wasted resist and the solvent, and T is a temperature of the wasted resist. 18. A method of resist coating according to claim 14, wherein said calculating a resin density is based on an expression as follows: Y=(CT+D) LnX+ET+F, wherein Ln is a natural logarithm, C, D, E and F are coefficients determined by compositions of the wasted resist and the solvent, T is a temperature of the wasted resist, X is the electric current value, and Y is the resin density. 19. A method of resist coating according to claim 14, further comprising supplying gaseous nitrogen to the tank.