Stressproof is a good choice. Machines beautifully and has excellent strength, and can even be heat treated if necessary. Even in the annealed state it just might outlast gears made of gray iron.
H
Moderator: Harold_V
Stressproof is a good choice. Machines beautifully and has excellent strength, and can even be heat treated if necessary. Even in the annealed state it just might outlast gears made of gray iron.
Yep! It can be put to use in the as prepared condition, as it is created to be used that way, but heat treat is not unreasonable. The 44 in its designation indicates that it should respond perfectly well to the carbon cycle method of heat treat, and would benefit by greater hardness, reducing wear. It also benefits by an increase in tensile strength, albeit at the cost of ductility.
Something I can verify, thanks to personal experience. Many years ago I had a sub-contract to machine punches for an ammunition disassembly machine for the Army. The punches were made of Stressproof (specified---one does not have the option of choosing materials when working for the defense department), and heat treat was very much a part of the requirement. A good number of them did crack in the process, which I attributed to the method by which Stressproof is produced. Its properties are developed by severe cold working, which, no doubt, create considerable internal stress. I don't overlook the possibility that there can be cold seams developed, either.Although, it does also state "a magnetic particle inspection operation should be performed after heat treating" due to possible quench cracking.)
I really can't see how it could work. The distance between the bottom of the teeth and spline is pretty small. Which leaves very little material on either piece.Torch wrote: ↑Sat Dec 12, 2020 8:50 pm I don't know. If Harold is right about it being grey cast iron, I'm not sure that press fit is a great idea. There's just not much meat between the major diameter of the splines and the root diameter of the teeth, and I don't think it will tolerate a lot of stress without cracking. Maybe a very light interference fit of 0.001" or less with some red locktite? A steel gear ring with the cast iron spline insert might be better.