Nice, I'd like give an SR101 a whirl then! I gotta hand it to fellas who spend so much time forging steel and finding new more efficient super steels. My dad is a pipefitter and even he is not familiar with SR101 or the mysterious INFI.
INFI, SR-101 and SR-77 are proprietary "NAMES" made up by Jerry. The steels themselves are somewhat (possibly / unknown) proprietary as well.
But, in general:
INFI: is appears to be unique and a (most likely) a true proprietary steel. I have not yet seen any steel that has similar composition to INFI's. Some speculate that is is based on A-8 chipper steel. But, the compositions vary considerably and I don't really see or understand the comparison of INFI to A-8 (?????)
SR-101: is basically "52100" - that is "rumored" to be "modified", but there is no "known" information to support any modifications to the steel composition other than a proprietary heat-treatment.
SR-77: is basically S7 - that is "rumored" to be "modified", but there is no "known" information to support any modifications to the steel composition other than a proprietary heat-treatment.
Most knife-makers and other people knowledgeable about forging and uses for steel will concure that Heat-treatment is a HUGE part of what makes any given steel great for "intended" purposes - whatever those purposes are.
Busse has earned HUGE respect for their ability to make GREAT knife steel and provide "consistantly" great steel. Toughness is VERY high while still providing very good edge properties. <img src="/ubbthreads/images/graemlins/thumbup.gif" alt="" />
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