Micromolding Takes On Macro Challenges

Very interesting...looks like a real specialised area.

Can't help wondering if there are more suitable techniques, maybe some way of cold forming using metal powders or some way of using the plastic withou having to melt a load of it...such a small volume of plastic would take very little heat to melt it, if that heat could get to the right place at the right time...?

Designing these machines must be really testing, but serious fun.

Del

You are right Del,

there are the established technologies of

metal-injection-molding,

micro casting ,

micro-galvano-forming,

micro-forging,

micro-turning, -milling, -grinding,

micro EDM, ECM.

Any of these has its specific pros and cons.

We have done microgrinding to fabricate the world smallest milling tools, endmills with only 10µm diameter, used to mill small trenches in ductile material (Plastic, brass, bronze, steel, titanium...).

And the same grinding coupled to galvanic nickel deposition to fabricate small grinding tools (any rotary shape, smallest diameter 10µm) to be used in grinding silicon, quartz and other oxides.

With these we can fabricate the molding tools necessary for micromolding.

To fabricate the tools is costly, to fabricate the mold is costly, to multiply the mold by ordinary (plastic material) injection molding is cheap (a suitable machine is not cheap).

Modern optics are often made this way. (Viaoptic)

To multiply the plastic mold by galvanoforming is not really cheap nor really expensif so very small toothed gears are made this way (Micromotion).

Most parts in use today (made by these technologies) are not really "micro" but micro is sexy today, so many non micro working people claim they do it.

RHABE

Cheers!

Great info.

When I read the article I immediately thought of the optical zoom in a digital camera.

Del

Another important challenge that face this emerging technology (including micro manufacturing metals/plastics using other micro-technologies) is in the area of design. Scaling effects have a big influence and there is a definite knowledge deficit. There is a need for investment by software companies to develop new modelling tools for this emerging industry. i.e. micro-mold flow analysis.

Also, material suppliers of the macro world do not what invest money in development of materials for micro world due to the small quantities required. There has been allot of research done on the effects of grain structure (both metals and plastics) on micro components. However, little has been done on the suppliers side.

I work in a mid-sized automotive facility. The amount of plastic delivered to this site this week is probably enough to keep the world's micro molding activities going for the end of the year.