What are the disadvantages? The article left those out. https://en.wikipedia.org/wiki/Semi-solid_metal_casting says it's "typically used for high-end applications" which suggests that it's very expensive. https://en.wikipedia.org/wiki/Semi-solid_metal_casting#Disad... says this is because it requires much more precise control over process parameters.

This augurs well for SSM casting, since precise control is immensely cheaper in 02021 than it was in 01977.

As I wrote below machines are n-times more expensive, and alloys themselves are far from being common, or cheap too.

Thank you very much!

The article hints that this is the process used to cast car frames, and does not mention Tesla by name. The pressures required in this method require actual dies, and not the sand casting that is within the range of the home shop.

Interesting things to know, but not something directly applicable to me. Thanks for posting it.

It's not like Tesla is anything special there, except for buying Italian-Chinese industrial caster for their product line, probably heavily due to being in the right time (combination of availability and building new line for a fresh product meaning they could do new design).

Tesla is using high pressure casting which, which supposedly, as per article, is more expensive, requires larger machines, wears out molds faster and requires additives than semi-solid casting.

Some background to it.

For laptop sized parts, semi-solid rheocasting,thixomolding is much cheaper than conventional casting on per part basis, and usually gives you superior fine features like studs, ribs, thin walls, and thus greatly reducing the need for final machining.

Downside is that semi-solid casting/molding machines are much more expensive than conventional ones because of powerful hydraulics, up to few times as much ($300k-$600k for making CE parts,) and the cost grows much faster than the maximum part volume. The alloy for them is also much more expensive than common aluminiums.

But on scales of consumer electronics manufacturing, material costs are minuscule in comparison to everything else, and the net shape capability is 100% worth the premium.

Both techniques will give you equally high material strength, but you will be paying much more for quality for conventional casting, to the point the cost advantage is lost.

Stronger low silicon alloys will need higher casting temperatures, and pressures to compensate for lower castability, and will also need degassing equipment, more expensive molds, and more extra equipment in general.

On the size of car chassis, I may bet the material cost will start to make a difference.

As a rule, you will need a lot more extra material to compensate for overall lower strength of cast parts.

>machines are much more expensive

So it is basically a CapeEx issue? Are there any other drawbacks?

He also mentioned the material itself is much more expensive.

I mean apart from BOM / COGS. Because CapEx shouldn't be really a problem when capital is as cheap as today's. And it offer a lot of other benefits, higher quality, better finishing etc.

It seems to be on paper, if you are working on a small item, with a target market of non-bottom quality product where you have a chance to charge a premium, this seems to be a no-brainer.