Stainless steel & vibratory tumbling: work hardening?

[Arthur.Marks]

Another one for the vibratory bowl topic. I'm smart enough to know not to use the same media that once deburred steel with stainless parts, but is there anything else to be aware of? For example, does ceramic media work harden the surface of 304SS parts? If so, does using an abrasive media with a softer bond---plastic resin, to name one---stop that from happening? Any other possible effects to be aware of?

[ckelloug]

Shot blasting definitely hardens things. The effect is called shot-peening and is sometimes exploited to work harden the outer surface of parts as a sort of low tech case hardening. Vibratory media probably does shot-peen too but to a much lesser extent. I remember seeing an equation about this in school but have long since forgotten it.

[topct]

Another one for the vibratory bowl topic. I'm smart enough to know not to use the same media that once deburred steel with stainless parts, but is there anything else to be aware of? For example, does ceramic media work harden the surface of 304SS parts? If so, does using an abrasive media with a softer bond---plastic resin, to name one---stop that from happening? Any other possible effects to be aware of?

Since no heat is generated then I doubt any surface hardening would occur. Your basically just sanding it with finer and finer grit.

The only surface hardening problem with 304 that I have experience with is with machining it.

[Cheeseking]

304 work hardens. Heat has nothing to do with it.

[ckalley]

The last place I worked, they used to viberatory tunmble 316 SS (small welded assemblies) all the time. Never had any problem with work hardening.

We used SS media with compound (soap, more or less) & water.

Craig

[Arthur.Marks]

I guess I will have to experiment before committing on customers' parts. The next question would have to be: does work hardening have any detrimental effect to the weldability of 304SS? or if brazing it?

[Clevelander]

Just a heads up..

I can tell you that I know very little about stainless steel, but I saw a post the other day that indicated that the 304 is relatively hard to machine compared to the 303. Would the 303 be an acceptable sub for your customer that will make your life easier.

Work hardening can be a remarkable thing. It's been so long that I'm not sure what metal it was that I was drilling, I think it may have been aluminum and I paused to take another bite....it was incredible the difference it was suddenly like trying to drill a hard grade of steel rather than a piece of aluminum.