What is the best steel for a knife?
Preference is everything. 1095 Cro-Van is legendarily tough, but that’s about it. AUS-8A resists corrosion and sharpens easily, but also dulls easily. 440C is a standby for knife steels and a reliable all-around performer, but is susceptible to corrosion. Any of the Cr, or MoV, series of steels from China are value alloys that generally perform well at their price points. S30V is considered one of the best all-around knife steels, with the best balance of edge retention, hardness, and toughness, but it’s expensive and generally reserved for premium blades.
Tl;dr: Every knife steel has advantages and disadvantages. It depends on what you need it to do and what you’re willing to spend. Personally, I’ve found I favor CPM 154 for EDC knives due to its edge retention and ease of sharpening.