Nanotubes

Afternoon all. I am a newbie to the IM space and looking for some insight. I cannot give a lot of details, but long story short is...my company is looking to develop a product that is typically steel. We are running into issues. We need the wall thickness of the product to be .020 - .030 in order for internal parts to function properly. The issue is the 3D prints are extremely weak at that level. We have found printing at .040 wall thickness yields the rigidity desire, but now effects internal parts. So my ask is if anyone knows of a mixture that can increase strength of the polymer? I have read about carbon nanotubes. Also mixing in tungsten powder maybe? Also see Torlon is used in automotive internals. I am not an engineer so bare with me if this is too generic.

Hello,
3D parts do not have the strength of molded parts. They are only to show and tell, some form and fit - not much function. So unless you mold you will not know for sure. It is best to talk to a material supplier and they will give you suggestions of fillers that you can use to get the strength. As I see it, you are 'almost' there and so should not be too difficult.
Let us know.
Suhas

You start by mentioning IM, but then say the part is 3D printed. Is printing the permanent method of manufacture or just prototyping with the intention of molding later? Printing will limit your choice of polymer and results may not be equivalent to a molded part.

Pay attention to part design – avoid stress risers like sharp corners.

You ask for strength but also talk about rigidity. These are not the same thing for plastics. Make sure you understand your requirements.

What is the base resin? Plastics are not created equal – PEEK is a lot stronger and stiffer than HDPE for example. Just because your printer will work with it doesn’t make your plastic the right choice for the product.

Nanotubes are expensive and typically used in low loading proportions for ESD applications. Powders typically won’t help much with strength, although they can add stiffness. Torlon is not melt processible.

All that said, you can get much higher strength and stiffness with just about any plastic by adding high loadings of either glass or carbon fiber (30% CF or up to 40% GF is not uncommon). Whether your printer will handle them is a different question.