I've been looking at axes, including axes for sale on the internet, forging, and materials. Most forged axes are made from low carbon steel, with a bit of high carbon steel inserted and welded into the blade.

I think they all have this wrong.

Why would you want to have any part of an axe head soft? Most people will tell you that you don't want it brittle, but guess what - just like with knives before you can apply enough stress to fracture something brittle, something soft will have already bent.

Let me say that another way. Take two pieces of steel - knives, axes, axles, doesn't matter what they are. Heat tread one to Rc 40 and the other to Rc 55. However you want to misuse them the harder one is going to take more abuse. The mode of failure will be different - maybe a bent blade is more useful than a broken one, but they're both failures.

The exception on an axe is the poll - if you're going to hammer steel with the back side then you want it soft enough to not chip.

The only "real" reason to do this is that the parts of the axe head away from the blade do not need to be stronger, so it's more efficient to use cheaper material. But it's much cooler to say you do it for ductility than for economy of materials.

As for carrying this over into knives, I think ductility in a knife blade is hogwash, other than making blades for the American Bladesmith Society tests. For a working blade the whole thing should be hardened. Of course people who spend a few hundred bucks for a custom forged knife like to see a hamon so that's what really drives it.

I should also restate my thoughts on knives vs. axes - knives are for cutting, axes are for chopping, sticks or crowbars are for prying. I think "chopper" knives in the survivalist sense are silly.

I'm going to do some forging this spring, maybe I'll make an axe head and test out my theory. Or maybe I'll come around to the other way of thinking when I start pricing big chunks of high carbon steel.

ETA: You can have an axe too hard - unless you're willing to give up sharpening it with a file.