A search of patents on the topics involved yields one that most closely resembles what is pointed to as supporting the claims made, i.e. based on studies done at U.S. Steel Corp, involving 52100 carbide and grain refinement via deviations from the standard single heat to austenitize and quench. Patent No. 3,337,376, Patented Aug. 22, 1967 “Method of Hardening Hypereutectoid Steels”, Raymond A. Grange Township, Westmorland County, Pa., assignor to United States Steel Corporation, a corporation of Delaware, Filed Dec. 27, 1966, Ser. No. 604,640. In his method Grange lays out a process using “pre-treatments which refines the carbides so that the final quench a can be done without concerns for their size or the retained austenite that could result in dealing with them at that time. This resulted in “a martensitic structure with an austenite grain size finer than ASTM #10 and a dispersion of uniformly fine carbides”. But there are two problems- 1. The phase most preferred before the final quench was bainitic or, at the most, a somewhat duplexed structure with some martensite resulting from an up-quench from below Ms to produce the bainite, i.e. the process bears little resemblance to “triple quenching” as described by bladesmiths. 2. The so called “theoretical limit” of grain size 10 is blown out of the water in 1966 at least! Could these, and other tricky points, be the reason that the Patent is often referred to but never entirely identified?
Stickels, while working for Ford Motor Co. followed up on Grange’s work with his study of “Carbide Refining Heat Treatments for 52100 Bearing Steel” In which he demonstrated increases is several areas of bearing performance by the refinement of carbides in the absence of increased retained austenite. Stickels seems to have come up with a more streamlined and effective version of Grange’s procedure using bainite or fine pearlite, with no martensite, as the prior prepared microstructure that is austenitized for the hardening procedure. It is interesting to note that very little in his writing is spent on grain size, possible because he recognized the greater significance of carbide refinement, or ultra-fine grain was mundane enough not to require special mention
