Cliff Stamp
BANNED
- Joined
- Oct 5, 1998
- Messages
- 17,562
[1/2" 440C tougher than 1/4" INFI]
No, you don't gain much impact toughness with thicker stock, strength goes up rapidly fast, but not impact toughness and flexibility actually goes down.
David Boye had some massively thick blades, 1/3" thick at the spine, but they sharpened very easily and cut very well on a lot of materials because of the primary and secondary grinds. The spine thickness of a blade is only going to matter if the material actually "sees" it. If you are cutting 3/8" hemp for example, pretty much all that matters is the edge angle and in particular is most sensitive to the microbevel.
Not that I would argue for putting that kind of deep hollow grind on a 1/2" thick 440C blade, or even that thickness in that steel in any grind, that is definately a case for a shock steel, or at least one of the spring or high impact A series steels. Imagine chopping heavy with that blade and hitting something hard with all the weight and speed of that massive heft behind it and having the edge unsupported by a hollow grind.
There are lots of types of cutting where edge holding increases with toughness, wood chopping for example. Now often to gain wear resistance you have to trade impact toughness, but edge holding doesn't always correlate well to wear resistance and even even this relationship is broken readily, CPM grades can have better toughness and wear resistance at the same time due to more homogenous structure for example as can changes in carbide structure which reduce aggregation and increase individual carbide hardness (Cr to vanadium for example).
As for being the "best", someone has to, just define the characteristics used to judge performance and their weights, then they can be measured and values assigned, people do it all the time, every single day. Of course everyone is free to chose what they think is important and just how important each aspect is to them.
-Cliff
Cobalt said:
No, you don't gain much impact toughness with thicker stock, strength goes up rapidly fast, but not impact toughness and flexibility actually goes down.
David Boye had some massively thick blades, 1/3" thick at the spine, but they sharpened very easily and cut very well on a lot of materials because of the primary and secondary grinds. The spine thickness of a blade is only going to matter if the material actually "sees" it. If you are cutting 3/8" hemp for example, pretty much all that matters is the edge angle and in particular is most sensitive to the microbevel.
Not that I would argue for putting that kind of deep hollow grind on a 1/2" thick 440C blade, or even that thickness in that steel in any grind, that is definately a case for a shock steel, or at least one of the spring or high impact A series steels. Imagine chopping heavy with that blade and hitting something hard with all the weight and speed of that massive heft behind it and having the edge unsupported by a hollow grind.
Quiet Storm said:
There are lots of types of cutting where edge holding increases with toughness, wood chopping for example. Now often to gain wear resistance you have to trade impact toughness, but edge holding doesn't always correlate well to wear resistance and even even this relationship is broken readily, CPM grades can have better toughness and wear resistance at the same time due to more homogenous structure for example as can changes in carbide structure which reduce aggregation and increase individual carbide hardness (Cr to vanadium for example).
As for being the "best", someone has to, just define the characteristics used to judge performance and their weights, then they can be measured and values assigned, people do it all the time, every single day. Of course everyone is free to chose what they think is important and just how important each aspect is to them.
-Cliff
) but because I decided to put this one into my bug-out bag.
