Bubba,
You're forcing me to think back over 20 years! Like most I hung around with, weekend drag racing, offroad 4x4s, and tractor pulling consumed much of my youth (and $$). Had to call some guys I didn't know were still in the area for this one.
Never worked with the 1541H before, at least not outside the form it was already in (axle).
But I don't see why it wouldn't make a good starting point for further experimentation; probably something I need to check into myself.
It is widely used in aftermarket axles due to the fact that, properly treated, it can provide about 25% more strength versus the standard 1040.
The "standard" for OEM axle material was 1040, sometimes possibly 1050.
Reading between the lines is often dangerous, but simply put, 1541H is a steel with same approximate carbon content as 1040, with added manganese.
As you suggested, the manganese does allow deeper hardening than carbon alone. For the most part, axles are not hardened completely through (unless we have an alloy steel). The deeper the hardening effect, the stronger the axle.
This allows a stronger part without making the part physically larger. Increased mass (larger axle diameter) is the first logical answer; compare a passenger car to anything made for abuse (HD truck, tractor, etc.) and that becomes obvious.
But in a performance application a physically larger part also means the penalty of increased weight.
Plus, having to work within the physical confines of an existing housing and axle tube design means you can only go so much bigger before you are forced to go "better".
For applications requiring even more strength than the 1541H, steels like 4140 & 4340 (chromemoly) are used.
I suppose there is also the possibility that an OEM could have used 1541H for certain applications as well, but I don't currently know of any specific instances. (Not that none have, just that I don't know.)
I can certainly see where it would be applicable to military vehicle use.
Keep in mind that 1541H is an SAE designation. I say this because, to the best of my knowledge, the "H" suffix denotes that the steel satisfies hardenability requirements, and is not necessarily an indicator that the steel was intended specifically for hot work.
Sounds confusing; after all, most of us are familiar with hot work steels like H13! But in those instances, the H is a prefix (in front of numerical identifier).
So essentially we're talking about a carbon-manganese steel, yet not quite an actual alloy steel. But the high manganese content allows response to heat treatment like alloys (deeper hardening, improved strength) so SAE moved steels like this from the 10xx series and gave them the designation of 15xx.
Still, from what I understand, 1541H is still marketed as a carbon steel, even though it in many ways behaves similar to an alloy.
How easy is it to work for your purpose? Well, axles made out of it are usually drop forged and induction hardened.
I don't see where it's anything you couldn't handle; after all, it's not like you're forging an air-hardening steel.
If you have access to a track nearby, a budget racer can probably find you a broken axle to experiment with. The weekend bracket racer, street/strip type is who I would check with first. (Most of the "big boys" are running chromemoly axles out of necessity.)
Another source is the guys running the offroad driveline shops. Tall tires place tremendous demands on axles, and most of the aftermarket replacements are 1541H. Even with the increased strength, it's common to face a broken axle every season. If such a shop can't find you a sample, at they very least they should be able to offer guidance on working characteristics.
A deeper hardening 1040? hmmm...:les:
Rob
edit to add: Much of the information concerning the steel was sourced from a guy who used to build chassis for me. I also contacted the owner of a local driveline shop, and both seem to be on the "same page". Both also admitted that, although they've never done it, the material would probably be good for a hammer.
If you need more, let me know; I'll see what I can dig up.
