Razor blades and process for making same

Abstract

Abstract THIS APPLICATION IS CONCENTRATED WITH PROCESSES FOR PRODUCING NOVEL STEEL WHICH, IN ITS FINISHED FORM, IS AT LEAST 80% AUSTENITIC AND IN PREFERRED EMBODIMENTS IS SUBSTANTIALLY FULLY AUSTENITIC, BUT YET HAS AT LEAST THE HARDNESS AND STRENGTH OF HIGH CARBON MARTENSITIC STEELS. THE HARDNESS OF THE STEEL PLUS ITS TEMPER-RESISTANCE (DUE TO THE FACT THAT IT IS AUSTENITIC) MAKES IT ESPECIALLY USEFUL FOR MAKING CUTTING EDGES, E.G. KNIVES AND ESPECIALLY RAZOR BLADES HAVING IMPROVED TEMPER-RESISTANCE. THE STEEL IS MADE BY (A) HEATING A STEEL COMPRISING FROM ABOUT 7 TO ABOUT 30% MANGANESE AND ABOUT 0.6 TO ABOUT 1.;% CARBON TO AT LEAST THE AUSTENIZING TEMPERATURE TO MAKE IT FULLY AUSTENITIC AND TO DISSOLVE SUFFICIENT CARBIDES SO AS TO DEPRESS THE "MS" TEMPERATURE SUFFICIENTLY BELOW ROOM TEMPERATURE THAT THE STEEL WILL REMAIN MAINLY IN THE AUSTENITIC FORM, E.G. AT LEAST 80% AUSTENITIC, WHEN IT IS BOTH COOLED, PREFERABLY BY QUENCHING, TO ROOM TEMPERATURE AND SUBSEQUENTLY COLD-WORKED; (B) COLD-WORKING THE STEEL AND (C) THEREAFTER AGE-HARDENING THE STEEL. IN A PREFERRED PROCESS FOR MAKING RAZOR BLADES FROM SUCH STEELS, THE CUTTING EDGE IS FORMED BETWEEN THE COLD-WORKING STEP AND THE AGEING STEP.

Inventors

• 👤 Sastri A Suryanarayan

Bibliographic Details