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Ceramics enter a new era with laser-welded joints (arstechnica.com)
149 points by joshlegs on Aug 30, 2019 | hide | past | favorite | 22 comments



For those wondering why this matters:

One reason is for electronics in extreme environments. Glass/Ceramics are more energetically stable than metals, so can withstand much higher temperatures. Think advanced sensors inside a rocket combustion chamber... while it is on.


I would add that there is a case for ceramic matrix composites in modern gas turbines. And this could also radically alter the ease of manufacturing for solid oxide fuel cells, which in addition to having extremely high combined cycle efficiencies (>80%), can natively use existing hydrocarbon fuel sources, as opposed to just pure hydrogen.


Is this what GE is putting behind the 9X to reduce noise?


It is used for the turbine blades and combustion chamber, but it has more to do with heat tolerance and weight than noise. I think the biggest part of the noise reduction comes from using a much larger and more efficient fan.


That is huge as it enables highly accurate feedback for instantaneous propulsion control.


With the ability to weld glass to metal and now ceramic welding, the next 50 years are going to see a manufacturing revolution.


Super critical water oxidation has been a benchtop process for quite a long time. As far as I’m aware they pretty much only use it for dealing with super toxic sludge these days, presumably because it’s too expensive to use for anything else.

It can burn just about anything which is why it’s difficult to get the ceramic pressure vessel right. Wondering if this will do anything to improve the situation.


This seem to need very high precision and until you can hand weld it, it will have limited applications comparing to Steel


Steel is routinely welded robotically. There are a very large number of applications where this advance in materials science will make a very large difference, keep in mind that:

- ceramics are thermally quite stable (with respect to expansion/contraction)

- ceramics do not conduct electricity

- ceramics do not melt easily

- ceramics are hard; leading to excellent longevity

- ceramics are chemically very stable

This is a pretty major thing.


I agree with you that it's a big deal to be able to do it, but I am pretty sure it'll stay specialty and extremely expensive for a long time. Brazing is good enough for a lot of things after all, just not so much against corrosion or super high temperatures.


I wonder if this might be a possible step on the way to the "magic plumbing" that molten-salt thorium reactors apparently need?


For someone without experience or the context of manufacturing, could you clarify why we will see a “manufacturing revolution”?


Not OP, but generally, breakthroughs in cost, processing, treatment, and/or properties of materials can have a tremendous impact on use.

If you think about it, up until about 1800, virtually everything humans made was made of stone, earth/brick, small cermic items, wood, plant fibres, animal fibres, glass, or a few easily-worked metals.

Since 1800, vast amounts of iron, steel, aluminium, concrete, titanium, plastics, composites (usually fibre + resin), processed woods, paper, glass, and ceramics have entered into use. We build things that simply couldn't exist or perform 200, 100, or even 50 years ago.

A common problem with metals is that they're either hard to process, or rare. Ceramics are based on very available silicates (though specific properties may rely on very high purities or rare forms), and are fairly easily processed. They do tend to be brittle and handle poorly under tension, or under vibration.

Your question's likely usefully answered in terms of past revolutions in manufacturing and construction: the stone arch, Roman concrete, Egyptian pyramids, Gothic cathedrals, large warships (wood, iron, steel, aluminium), pipelines, motors, iron-framed presses and machinery, steel-framed buildings, copper-based electric motors and transmission wires, aluminium and aircraft, titanium and supersonic / hypersonic aircraft and missiles, glass and optics, plastic and mass consumer goods, silicon and electronics, artificial fibres and modern clothing.



I was hoping to find a ceramics fusion welding technology while I was researching thermionic converters. I thought it was impossible. Glad to see someone figured out how to do it!


What were you making thermionic converters for?


Just personal interest in converting heat to electricity. I saw a demo of it on youtube and it seemed simple in principle. The materials required are often superlative and hard to master.


This is very interesting. Anyone have a good article for laypeople about the modern use of ceramics in making things. I tried googling but failed.


What sort of applications would this be used for? I see in the article housing electronics, but isn't plastic pretty good for that? Aren't ceramics super brittle?


Plastics don't work well in some environments, space and medical situations usually. This might make for some better (less bioreactive) and cheaper (instead of titanium) implantable devices. Plastics in space tend to have a few issues that I know of, off-gassing and UV degradation in particular.


I'm thinking the ceramics would cancel lots of the electrical noise that electronics, and electrical components, put out. You can't have a very sensitive antenna if all the components in a receiver are spewing lots of electrical signals.

Making it possible for even smaller computers.


Thinking of it... Recycling of these computers will be challenging - how do you dispose an item made from "unobtanium" ?

Crush it into sand? It is one of the hardest materials, one needs a harder material to crush something. Heat/cool to have it crumble does not work well either with ceramics.

Melting it into glass or something? Might not be practical due to extremely high temps required.

Using it as "pebble" in road/bridge construction? Not sure if concrete will be able to stick to it.




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