does fine powder stainless steel burn?

[Bruce Boone]

I'm interested in doing experiments with selective laser melting on stainless steel, but don't have a clear answer on if fine powdered stainless steel can burn. I assume if the sphere size is large enough it wouldn't. I've read that the super fine stuff, like 5 micron sphere size will be influenced a lot by electrical and magnetic issues. A more realistic 40 micron size doesn't have as many issues with that. I've found a place that does supply all sorts of fine metallic powders in literally hundreds of alloys, but they seem to put a blanket statement that any fine powder chemical may burn, so you pay the extra $100 for shipping any amount, even 200 grams. The MSDS for 3D Systems powdered stainless lists the flammability at 0 out of 4. I don't know if they are doing something different or not. I don't want to risk burning up my laser or paying hundreds of dollars on something that may not work at all. I know titanium and aluminum require an argon shield system, but I don't know about stainless steel. Anyone have any insight about this?

[Mike Null]

Bruce

Maybe Synrad can offer some insight. http://www.synrad.com/search_apps/application_briefs/56-3.htm

[Dave Sheldrake]

Laser sintering Bruce?

cheers

Dave

[Bruce Boone]

Yes, that's what I'm attempting. I have done it with bronze powder before. It did make solid 2D letters on the YAG, which has a galvo setup. I didn't do multiple layers or anything, but if I could do a nice strong metal like titanium or stainless, there's a good chance I could build a low cost system for it and actually utilize it to do some crazy ring designs. I imagine stainless should only be easier than titanium as titanium is very reactive and burns easily. I do have some metal clay powders (Hadars clay) made for jewelry. I can experiment with that I suppose. It's not meant for sintering or welding, but it might be a starting point.

[Dave Sheldrake]

http://www.lasersintering.com/sls-material.php

Not sure if that is any help Bruce?

[Bruce Boone]

That does have good info on minimum layer thickness and other things. I still don't see anything about the flammability there though.

[Dan Hintz]

Considering you can set steel wool on fire with a battery, I'd say it's a very real possibility.