Hitachi Blue 2 Knife Steel
Composition Analysis Graph, Equivalents And Overview

Blue 2(Hitachi) - Ref. Kitchen Knife Steel FAQ - Also referred as Ao-Ko II. Hitachi high carbon steel, specifically developed for tools and knives. Very pure alloy - P <= 0.025%, S <= 0.004%. In my experience very good steel, just like its brother Aogami 1 steel. As mentioned above, it's slightly tougher compromising wear resistance a bit. Although, at those levels of hardness 63HRC and above, the difference is really hard to tell, at least in home kitchen use. My Watanabe Honesuki is made out of Blue 2, one of my favorites too, Kumagoro Gyuto is also made out of it. Aritsugu also makes his high end knives from blue 2, I have only very positive experience with his Honkasumi Yanagi and Fugubiki, both blue 2, 65HRC+. Last few years there's a trend I've noticed, more makers are switching to Aogami 2 from Aogami 1. It's a bit tougher and because of that it's less likely to suffer damage at the hands of the neglectful or inexperienced users, and performs almost as well as Aogami 1.

Manufacturing Technology - Ingot

Country - Japan(JP)

Known Aliases:
Hitachi - Aogami 2, Hitachi - Aoko 2, Hitachi - Aoniko