Blade flex question

[CUTS LIKE A KRIS]

OK- so I get that each steel flexes to the same degree no matter the hardness. So to further this, is there a list that any of you intelligent gents could give that goes from least flex to most flex in regards to blade steels.

I have noticed that there is a great deal of difference between my 3/32" Carbon V fillet knife (flexable) and my 1/16" 12C27 (rigid).

Just something to help us newbies out when looking at the different properties to choose our steel.

Thanks

 

[Rody]

If you mean stiffness (x amount of deflection for y amount of force within the elastic range), there's virtually no difference between steels to my knowledge. They all have pretty much the same e-modulus which, combined with the geometry of the blade (notably cross-section), determines stiffness. So in your case the geometry must be the determining factor. It is strange however that the thicker blade is more flexible since, given the same outline of the blade and the same bevel, the 3/32 blade should be nearly 3.5 times as stiff as the 1/16 blade....((3/32 / 1/16) ^3). Do you have a side-by-side picture of the two knives?

Cheers Rody

 

[Don Hanson III]

Type of steel does not matter, there has to be something different (profile, geometry, width, etc.) between the two blades to make the thicker one more flexible. Or it could be a tropical delusion

 

[Steve Hayden]

Type of steel does not matter, there has to be something different (profile, geometry, width, etc.) between the two blades to make the thicker one more flexible. Or it could be a tropical delusion

I like those tropical delusions-its been about thirty years since I had one, though...

 

[LRB]

As I understand it, you will get the same amount of flex in annealed steel as in hardened steel, at a given equal amount of force, to a point equal to the annealed steel before it reaches the point of no return. The elastic range. However, after that point, one is going to set bend, while the other is going to break. This is where different steels, with different HT, are not going to be equal in their ability to flex beyond that original given elastic range. Otherwise, we would not be able to make springs would we? At the degree, or force, the annealed piece set bends, the hardened piece is likely to break, whereas if tempered, it is going to continue to flex, with more force applied, to whatever the temper allows. How flexable it is after HT is going to depend on it's temper, and make up. NO, not all steels are going to flex equally after HT, whether equal in thickness, or not. It will depend on the temper, beyond it's given elastic range. That is pretty much common sense.

 

[Jared Stenoien]

Flex means no permanent deformation, so is by definition elastic. Beyond the elastic range that you're talking about it's bending.

 

[mete]

Jared, the confusion comes because of the different definitions used by non-technical types. The proper term is Modulous of Elasticity and is different for different metals [not different steel alloys]. So the M of E is different for iron, aluminum, titanium ! For knives thinner is more flexible so for flexible filleting knife you wan t a thin blade.

 

[bambright]

I guess the question might be at the optimum heat treatment, which steel provide maximum yield strength? meanwhile maintains the maximum toughness (strength)