Thread: heat treating stock axles

Originally Posted by JDNSW

The angles quoted assume the material is isotropic with the same properties in all directions, I question whether this is exactly the case for axle shafts, especially for induction hardened ones, although I agree the stress angles will usually be close to 45 degrees in practice.

I encountered one interesting failure (in a rear axle on a 6x6 IH R190) - failed about four inches from the outer end, with a clean break that looked as if it had been cut with a parting tool. It was a replacement axle for one that had failed with the classic spiral break starting from the end of the spline, and failed the first time low range was used after it was fitted, when it sank a couple of inches in very slippery mud.

John

Most I've seen are like that

Originally Posted by Slunnie

Most I've seen are like that

Same here - every 24-spline axle or CV stub I have broken or seen broken has looked like it was cut with a drop saw.

By comparison, 10-spline series axles break in a much more jagged pattern.

Originally Posted by isuzurover

Same here - every 24-spline axle or CV stub I have broken or seen broken has looked like it was cut with a drop saw.

By comparison, 10-spline series axles break in a much more jagged pattern.

I wonder if you are seeing the difference between overload failure (ten spline) and failure due to fatigue initiated at a stress concentrator such as a material flaw or surface defect (24 spline or CV stub)?

John