Infi steel?

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tryppyr said:
Here we go.

I predict a flood of fanboys defending the Busse name.
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joshiecole said:
The standard hard use Busse Combat grind is 40 degrees (inclusive)
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Someone had Infi zapped (X-ray diffraction) awhile ago, and it's within a decimal point of LaTrobe's A8 Chipper Steel (A.K.A. A8 Modified).
A great, tough alloy steel with a blunt cutting geometry == broken cinder blocks :)

http://www.latrobesteel.com/assets/documents/datasheets/LSS_Chipper.pdf

Infi.jpg
 
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jimmyjohnjohn said:
1. I still have the uncropped originals. They are about 5 megabytes and 5000x3000 pixels, so they are large. I'll have to find somewhere to host them. I may have to put them at a file hosting site like RapidShare. I'll take a look at that when I get home from work tonight.
2. I agree, from my experience anyway. I've already resharpened the edge and it will slice paper like a razor now.
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From the pictures you posted the degree of damage on the edge seems fairly shallow, though noticeable. Without holding it it's difficult to see what kind of damage some of it is. There's at least one circular missing section that in my limited experience does indicate a "chip" (like glass), but most of everything else looks like it could be a deformation or a tear out. In all of the broken busse's I've seen very few suffered chips, and those were always under extreme shock on very small sections of the blade (like when chopping a chain). The biggest chip I saw (out of three) was about 2mm in size. It's still a chip, but that the steel seems to avoid large chips when it does chip is important. The latter two types (deformation and tear out) are ideal in a high hardness knife (58-60rc) because deformations can be burnished back into shape to a degree and a tear out indicates that the steel deformed significantly before breaking away from the knife. That's a good thing because it shows that the knife diffuses the energy before breaking, the opposite of glass with it's complete lack of plasticity.

It's rare that a knife edge is able to take small hard impacts from sharp and jagged rocks without any sign of damage. INFI is no exception, it will take damage under such forces. It's the way it fails that's important. It maintains a fairly high degree of malleability at 58rc that allows it to take on shock forces and deform instead of chip - and once it does so it takes readily to burnishing to realign it.

farranger said:
I have a busse basic 7 and bought it because I'd heard so much good about it from my dad who liked his.
If I understand correctly, the basic 7 is a Modified infi steel, whatever that is.

I'm curious from you guys who know a lot more. You're supposed to sharpen only one side of the knife,
leaving the other side with a rounded edge?
Any thoughts on why that edge geometry? Sounds like some of you guys with a busse have sharpened
it to different edges?
Any suggestions for me on that edge. It's a basic survival type knife that at 7 inches I almost feel to self conscious
to wear the thing. I like four inch blades, don't know why I didn't buy the basic 5.
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What you have is busses 'assymetrical edge' which was only really used on the basic series. It's meant to be give part of the efficiency of a chisel grind, part of the strength of a convex bevel, and the ease of only having to stop the wide convex side and a few passes with a crock stick on the smaller flat side. It's meant to be easy to maintain in the field and a blend of efficiency and strength. Some love it and swear by it, many just think it's weird and sharpen it into a V grind.

jdm61 said:
They are not going to tell you that. Many folks think that is something akin to a modified S series steel with nitrogen added.
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lazlo said:
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Someone had Infi zapped (X-ray diffraction) awhile ago, and it's within a decimal point of LaTrobe's A8 Chipper Steel (A.K.A. A8 Modified).
A great, tough alloy steel with a blunt cutting geometry == broken cinder blocks :)

http://www.latrobesteel.com/assets/documents/datasheets/LSS_Chipper.pdf

http://i164.photobucket.com/albums/u15/rtgeorge_album/Infi.jpg
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INFI's composition has been known to the public for nearly 10 years. It's not a modified A8. Given the degree of difference in number of elements present and percentage of those differing elements: they look nothing alike.

(this is from a 3rd party spectral analysis of INFI)
INFI
C 0.5% Carbon
V 0.36% Vanadium
Cr 8.25% Chrome
Mo 1.3% Molybdenum
Co 0.95% Cobalt
Ni 0.74% Nickel
Mo 1.3% Molybdenum
N 0.11% Nitrogen
Fe 87.79% Iron

A8
Carbon - 0.55
chromium - 5.00
Molybdenum - 1.25
Tungsten - 1.25
 
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Last Visible Canary said:
INFI's composition has been known to the public for nearly 10 years. It's not a modified A8. Given the degree of difference in number of elements present and percentage of those differing elements: they look nothing alike.
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That's because you have the wrong steel. Try comparing Latrobe's A8 Chipper steel to INFI:

Infi-1.jpg
 
Very close, but not exactly. I think it is a measure of how much energy is absorbed when you swing a pendulum through the sample, measured by how far the pendulum continues its swing. You might be thinking of a tensile test.

Notched impact testing is a good judge of how catastrophic a failure will be, but a poor predictor of ultimate strength.
 
Nathan the Machinist said:
Very close, but not exactly. I think it is a measure of how much energy is absorbed when you swing a pendulum through the sample, measured by how far the pendulum continues its swing.
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We're saying the same thing: Charpy measures the amount of energy absorbed by a material during fracture. So you put a sample in the vise, and compare the difference in the height of the pendulum before and after the fracture.
It's a quantitative measure of toughness.

http://www.youtube.com/watch?v=l7OS3sDrnJo
 
lazlo said:
That's because you have the wrong steel. Try comparing Latrobe's A8 Chipper steel to INFI:

http://i164.photobucket.com/albums/u15/rtgeorge_album/Infi-1.jpg
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There are similarities and significant differences. 1%cobalt, nearly 1% nickle, .5% manganese and 1% silicon create a notably different alloy. My next question is when did LSS chipper steel come into existence? The pdf from latrobe is dated 2006, but Timken sold Latrobe in 2006 so it may just be that they updated all of their materials. I ask this because INFI has been present as a production steel since 1998 when busse produced the 60rc SHBM's, one of which was reviewed by hood in 'american survival guide'. Chances are it was in existence before then for testing, but the SHBM's were production models.

If latrobes LSS chipper steel came out later than INFI, how is INFI a modified LSS chipper? would it not be the other way around? Or at the very least, A8 being modified to be similar to INFI.
 
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Is Busse still in business?
Whatever INFI is, it works and it works very well. That's all the data I need.
 
FWIW I chopped through a downed tree that was on the trail last week and it was still sharp enough to shave hair off of my arm. I've never had a production knife do this and I don't have a need to bust up cinder block so this was all the test I needed.

DSC_6845.jpg

DSC_6849.jpg
 
Derek, this is a year old thread. Please look at the date before posting on a thread you pulled up in a search......Thread closed.
 
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