The Basics of Knife Steels: Part 1
If you're an average knife buyer, the type of steel used to make a knife blade is probably not a consideration when making a purchase. I think most people are confused by the different materials and hardness ratings. Let's see if we can clear things up a bit. Today and tomorrow, I'll write about the most common types of steel (and even some non-steel products) and what they're best suited to do. On Friday, I'll write about hardness ratings and what they mean and how they should influence your knife purchase.
440 stainless steel
Probably the most common type of stainless knife steel is 440. It comes in three varieties, which have different amounts of carbon and other metals they contain. On the low end is 440A, which has 0.65% to 0.75% carbon. On the high end is 440C, which has 0.95% to 1.20% carbon. All 440 steels are 16% to 18% chromium, which contributes to their stainless quality. Higher carbon means the blade holds an edge better. Ever notice how cheaper (low-carbon) knives get dull really fast? They're usually lower in carbon. Price isn't always an indicator of quality, but 440C knives tend to be more expensive than 440A. In some cases, the manufacturer doesn't indicate which 440 steel is used but will say it's "high-carbon" steel.
AUS stainless steel
Like 440 steel, AUS comes in several grades. AUS-4 is 0.40% to 0.45% carbon, but AUS-10 is 0.95% to 1.10% carbon. The level of chromium is 13% to 14.5% - less than the 440 varieties but still enough to ensure a stainless blade. Generally speaking, AUS-10 knives will be more expensive than the other three AUS varieties.
Next, we'll look at high-carbon steel and alternative knife blade materials.
Copyright 2005-2006 by Cheaper Than Dirt. Reprinted with permission
Return from Knife Steel Basics: Part 1 to Knife Making Supplies .net