Materials having high corrosive resistance to attack by fluorine at cryogenic temperatures and method of preparing them

Claim 2

A SINTERED FLUORINE RESISTANT COMPOSITE ARTICLE CONSISTING ESSENTIALLY (1) FROM ABOUT 80% CALCUIM FLUORIDE AND CORRESPONDINGLY ABOUT 20% BARIUM FLUORIDE.

Claim 3

A FLUORINE RESISTANT COMPOSITE ARTICLE CONSISTING ESSENTIALLY OF (1) FROM ABOUT 75% TO 95% BY WEIGHT OF A MATERIAL SELECTED FROM THE GROUP CONSISTING OF BARIUM FLUORIDE AND CALCIUM FLUORIDE AND CORRESPONDINGLY (2) FROM ABOUT 25% TO 5% BY WEIGHT OF POWDERED METAL SELECTED FROM THE GROUP CONSISTING OF COBALT, ANTIMONY, NICKEL, SILVER, IRON, ALUMINUM, TIN AND STAINLESS STEEL.

Claim 4

A FLUORINE RESISTANT COMPOSITE ARTICLE CONSISTING ESSENTIALLY OF (1) FROM ABOUT 75% TO 95% BY WEIGHT OF A MATERIAL SELECTED FROM THE GROUP CONSISTING OF BARIUM FLUORIDE AND CALCIUM FLUORIDE AND CORRESPONDINGLY (2) FROM ABOUT 25% TO 5% BY WEIGHT OF POWDERED METAL SELECTED FROM THE GROUP CONSISTING OF COBALT, ANTIMONY, NICKEL, SILVER, IRON, ALUMINUM, TIN AND STAINLESS STEEL.

Claim 5

A PROCESS FOR MAKING SINTERED FLUORINE RESISTANT COMPOSITE ARTICLES FOR USE AS BEARINGS AND SEALS WHICH COMPRISES CALCINING POWDERS CONSISTING ESSENTIALLY OF FROM ABOUT 75% TO 95% BY WEIGHT OF A 4:1 MOLAR RATIO OF CALCIUM FLUORIDE AND BARIUM FLUORIDE CORRESPONDINGLY AND ADDING THERETO 25% TO 5% BY WEIGHT POWDERED METALS SELECTED FROM THE GROUP CONSISTING OF COBALT, ANTIMONY, NICKEL, SILVER, IRON, ALUMINUM, TIN, STAINLESS STEEL AND COPPER; FURTHER REDUCING PARTICLE SIZE OF SAID POWDERS TO FORM A MIX; INTRODUCING SAID MIX INTO A DIE; APPLYING PRESSURE OF UP TO ABOUT 20,000 P.S.I. TO SAID DIE TO THEREBY FORM A COHESIVE SPECIMEN; REMOVING SAID SPECIMEN FROM THE SAID DIE, PLACING SAID SPECIMEN IN AN OVEN; AND HEATING SAID SPECIMEN AT A TEMPERATURE FROM 1500*F. TO 1700*F. FOR A PERIOD OF TIME TO SINTER THE SPECIMENS TO A POROSITY OF LESS THAN 0.5 PERCENT.

Claim 6

A PROCESS FOR MAKING SINTERED FLUORINE RESISTANT COMPOSITE ARTICLES FOR USE AS BEARINGS AND SEALS WHICH COMPRISES CALCINING POWDERS CONSISTING ESSENTIALLY OF FROM ABOUT 75% TO 95% BY WEIGHT OF A 4:1 MOLAR RATIO OF CALCIUM FLUORIDE AND BARIUM FLUORIDE CORRESPONDINGLY AND ADDING THERETO 25% TO 5% BY WEIGHT POWDERED METALS SELECTED FROM THE GROUP CONSISTING OF COBALT, ANTIMONY, NICKEL, SILVER, IRON, ALUMINUM, TIN, STAINLESS STEEL AND COPPER; FURTHER REDUCING PARTICLE SIZE OF SAID POWDERS TO FORM A MIX; INTRODUCING SAID MIX INTO A DIE; APPLYING PRESSURE OF UP TO ABOUT 20,000 P.S.I. TO SAID DIE TO THEREBY FORM A COHESIVE SPECIMEN; REMOVING SAID SPECIMEN FROM THE SAID DIE, PLACING SAID SPECIMEN IN AN OVEN; AND HEATING SAID SPECIMEN AT A TEMPERATURE FROM 1500*F. TO 1700*F. FOR A PERIOD OF TIME TO SINTER THE SPECIMENS TO A POROSITY OF LESS THAN 0.5 PERCENT.