[judleroy]

I have about 10gallons of rigid polyurethane for making cast parts. Can this be used to make epoxy granite? Next I have available a whole lot of steel , ss steel, titanium, hastelloy, inconel, and aluminum chips. Is there any issue with using them for filler material? Thanks for any advice.
Judleroy

[RomanLini]

I'm not an expert in casting "epoxymetal" but I have experimented with the aluminium and bronze fine powders (as sold for cold-cast fake metal ie sculptures). I have also messed about with using larger chips as a filler, by themselves and in combination with other fillers.

Pretty much any inert filler can be used in a composite. One thing you should watch out for is lubricant, it will make the bonds weak if there is any thing greasy on the chips. Also polyurethane is low adhesive so composite strength will always be weak compared to an epoxy which are generally high adhesive.

Another issue will be that the complex shape of most chips means that there will be a lot of epoxy by percentage, again that can make the composite weak.

[judleroy]

Thanks for the reply Romanlini. Are there any other things like sand and gravel I could use instead. Maybe those and the metal? Thanks
Judleroy

[RomanLini]

Anything which is inert (won't change) and is strong can be used as a filler and will make th epoxy much stronger. And it should be clean. Gravel, sand, nuts and bolts it doesn't matter that much.

But if you want to get high performance there are people with much more knowlege than me in making very high performance EG composities in the other thread (the BIG thread on EG).

[rocketflier]

I have about 10gallons of rigid polyurethane for making cast parts. Can this be used to make epoxy granite? Next I have available a whole lot of steel , ss steel, titanium, hastelloy, inconel, and aluminum chips. Is there any issue with using them for filler material? Thanks for any advice.
Judleroy

Do you mean rigid polyurethane foam? I don't think that will work.

[janaf]

I assume it is not foam, but maybe something like this:
Resin System Description for (Rigid Polyurethane) RTP 2300 Series Thermoplastic Compounds - RTP Company
There is a lot of data, case studies and datasheet for different fiber reinforced compounds.