Takefu VG-5

[Bodog]

Any experience? Thoughts?

[jabba359]

It appears to have only half as many VG's as my knives from Japan.

[Cheddarnut]

VG stands for Very Good, so its Very Five Good.

[The Mastiff]

Hi Bodog. I believe it was used some time back in the "tiger" something line of replaceable blade knives sold like a fancier sort of super knife. The steel is: http://www.e-tokko.com/eng_vg2_vg5.htm

It wasn't anything special in the tiger blades or whatever they are called but they were meant to be used and disposed so who knows what it would have been like with a top of the line heat treat. They group it with VG2 which is used as the cladding steel on ZDP if I'm not mistaken. The cladding on the" Super Gold" 3 ( or whatever Falkniven and earlier Kershaw called it). The "Super Gold" is itself Takefu made but a premium powder steel http://www.e-tokko.com/eng_original_list.htm They call that Powder steel Super G1 & G2 on the products page above so I'd suspect the clad steels are made there at the foundry itself. They also make the "cobalt special" steel as used in the Falkniven and Spyderco Mule team 9.

Joe

[Cliff Stamp]

The description is exactly what you find in patent for razor blade steels for VG2. It is designed with a specific C/Cr ratio to produce a very small amount of chromium carbide (3-5%), high hardness and corrosion resistance. VG5 adjusts the carbon content to produce a lightly higher hardness, wear resistance but compromises on corrosion resistance. VG-5 is similar to steels like MBS-26 .

The interesting thing about these steels is that the properties are very sensitive to how they are hardened. If you look at S90V for example then regardless of how it is hardened it will still have a massive amount of vanadium carbide and still have a high wear resistance and low grindability. However a steel like VG2 if not hardened very well ends up have a very low mix of properties all around and you would end up wondering why anyone though it was a good material let alone excellent one.

[KevinOubre]

The interesting thing about these steels is that the properties are very sensitive to how they are hardened.

Basically the 13C26 problems from Kershaw. That stuff sucked so bad from them

[Bodog]

Yeah, I was thinking it appeared to be very similar to MBS26 with higher wear resistance and probably a little more corrosion resistance.

"VG-5 is similar to steels like MBS-26 "

[Cliff Stamp]

Basically the 13C26 problems from Kershaw. That stuff sucked so bad from them

The funny thing about that was Landes had been talking about AEB-L and apex stability for quite some time and a number of people started to label what he said as "hype" which is nonsensical as he was quoting materials data. However when Kershaw came out with a production knife in 13C26 there were a number of "I told you so's" from the people who made the hype argument.

Of course Landes was always clear that the hardening was critical :

-pre-heat(s)
-close to very hot/flash soak
-oil quench
-deep cooling
-multiple low tempers

This will produce a very fine austenite grain, 3-5% chromium carbide, 62+ HRC and in general is a very nice steel for high sharpness edge holding, high durability (for stainless) and high corrosion resistance.

However if you don't do any of those you end up with :

-coarse austenite
-diffusional phases
-retained austnite
-carbide precipitation

The steel is then soft, weak, gummy, apex stability is low, wear resistance is low, and there can even be problems in chipping.