Hand Tools

Subject:
A point about Narex

Wiley Horne
Narex’s website tells us they use austempering techniques:

http://www.narexchisels.com/Narex_Chisels/Narex_Bystrice.html

Classic austempering means that the final product is not tempered martensite (like all your other chisels)—it is bainite. They don’t quench to a low enough temperature fast enough to produce martensite. The prime characteristic of bainite is that, at a given Rc, it is tougher than martensite. But it can’t be gotten as hard as martensite. There are techniques where the quench temperature is controlled right at the borderline where martensite begins to form, and you get a bainite/martensite mix. Narex claims fine grain also.

So it may be that Narex is favoring toughness and fine grain over hardness. Do they advertise an Rc spec?

Wiley

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