Method of making a composite bearing material

Claim 1

THE METHOD OF MAKING A COMPOSITE BEARING MATERIAL WHICH COMPRISES THE STEPS OF PROVIDING A HARD METAL BACKING STRIP, APPLYING A METALLIC POWDER LAYER TO ONE SURFACE OF SAID BACKING STRIP SINTERING SAID POWDER LAYER FORMING A COMPOSITE STRIP COMPRISING A POROUS SINTERED MATRIX HAVING A POROSITY OF FROM ABOUT 10% TO ABOUT 50% BY VOLUME WHICH IS TENACIOUSLY BONDED TO SAID BACKING STRIP, PROVIDING A HEAT SOFTENABLE PLASTIC CONSISTING ESSENTIALLY OF AN INTEROLYMER OF TETRAFLUOROETHYLENE AND HEXAFLUOROPROPYLENE INCORPORATING A SOLID FILLER DISPERSED AS DISCRETE PARTICLES SUBSTANTIALLY UNIFORMLY THERETHROUGH, HEATING SAID COMPOSITE STRIP AND SAID PLASTIC TO A TEMPERATURE AT WHICH A HEAT SOFTENING OF SAID PLASTIC JOCCCURS TO ENABLE EXTRUSION THEREOF, EXTRUDING THE HEAT SOFTENED SAID PLASTIC AT A PRESSURE OF FRO ABOUT 200 P.S.I. TO ABOUT 10,000 P.S.I. INTO DIRECT CONTACT WITH SAID POROUS MATRIX AND IN LATERAL CONFINED RELATIONSHIP WITH RESPECT JTO THE LONGITUDINAL SIDE EDGES OF SAID STRIP EFFECTING A CONCURRENT IMPREGNATION OF AT LEAST SOME OF THE PORES OF SAID MATRIX AND A COATING OF THE EXPOSED SURFACE OF SAID MATRIX WITH A SUBSTANTIALLY CONTINUOUS RESIDUARY FILM OF SAID PLASTIC, COOLING THE COATED AND IMPREGNATED SAID COMPOSITE STRIP TO A TEMPERATURE BELOW THE HEAT SOFTENING POINT OF SAID PLASTIC, AND THEREAFTER FURTHER COMPRESSING THE COOLED SIAD COMPOSITE STRIP EFFECTING A GAUGING THEREOF AND A SIZING OF SAID RESIDUARY FILM.

Claim 2

THE METHOD OF MAKING A COMPOSITE BEARING MATERIAL WHICH COMPRISES THE STEPS OF PROVIDING A HARD METAL BACKING STRIP, APPLYING A METALLIC POWDER LAYER TO ONE SURFACE OF SAID BACKING STRIP SINTERING SAID POWDER LAYER FORMING A COMPOSITE STRIP COMPRISING A POROUS SINTERED MATRIX HAVING A POROSITY OF FROM ABOUT 10% TO ABOUT 50% BY VOLUME WHICH IS TENACIOUSLY BONDED TO SAID BACKING STRIP, PROVIDING A HEAT SOFTENABLE PLASTIC CONSISTING ESSENTIALLY OF AN INTEROLYMER OF TETRAFLUOROETHYLENE AND HEXAFLUOROPROPYLENE INCORPORATING A SOLID FILLER DISPERSED AS DISCRETE PARTICLES SUBSTANTIALLY UNIFORMLY THERETHROUGH, HEATING SAID COMPOSITE STRIP AND SAID PLASTIC TO A TEMPERATURE AT WHICH A HEAT SOFTENING OF SAID PLASTIC JOCCCURS TO ENABLE EXTRUSION THEREOF, EXTRUDING THE HEAT SOFTENED SAID PLASTIC AT A PRESSURE OF FRO ABOUT 200 P.S.I. TO ABOUT 10,000 P.S.I. INTO DIRECT CONTACT WITH SAID POROUS MATRIX AND IN LATERAL CONFINED RELATIONSHIP WITH RESPECT JTO THE LONGITUDINAL SIDE EDGES OF SAID STRIP EFFECTING A CONCURRENT IMPREGNATION OF AT LEAST SOME OF THE PORES OF SAID MATRIX AND A COATING OF THE EXPOSED SURFACE OF SAID MATRIX WITH A SUBSTANTIALLY CONTINUOUS RESIDUARY FILM OF SAID PLASTIC, COOLING THE COATED AND IMPREGNATED SAID COMPOSITE STRIP TO A TEMPERATURE BELOW THE HEAT SOFTENING POINT OF SAID PLASTIC, AND THEREAFTER FURTHER COMPRESSING THE COOLED SIAD COMPOSITE STRIP EFFECTING A GAUGING THEREOF AND A SIZING OF SAID RESIDUARY FILM.