Posted on 03/07/2015 10:13:54 PM PST by Swordmaker
@marco_org Apple has a patent that can reduce the gold content of their 18k gold by half. veg.gy/ZhMF2
— Sumocat (@SumocatS) Mar 6 2015 1:58 PM
It’s inartfully put (140 characters is a bitch), but as a practical matter he’s correct. Apple’s patent application is for a method that allows them to make 18k gold that has, on a volume basis, less gold than regular 18k gold.
How can this be? It’s because Apple’s gold is a metal matrix composite, not a standard alloy. Instead of mixing the gold with silver, copper, or other metals to make it harder, Apple is mixing it with low-density ceramic particles. The ceramic makes Apple’s gold harder and more scratch-resistant—which Tim Cook touted during the September announcement—and it also makes it less dense overall.
The karat measure of gold is based on the mass fraction. One hundred grams of 18k gold has 75 grams of gold and 25 grams of other material. If that “other material” is a low-density ceramic, it takes up a bigger volume than if it’s a high-density metal. Because the casing of a watch is made to a particular size (i.e. volume), not to a particular weight, the Watch will have less gold in it than an 18k case made of a conventional alloy.
As an example, assume a conventional 18k gold alloy with 75% gold (19.3 g/cc), 15% silver (10.5 g/cc), and 10% copper (8.96 g/cc) by weight. The alloy will have a density of
A cubic centimeter of this alloy will contain
Now assume an 18k gold with 75% gold and 25% boron carbide by weight (that’s one of the ceramics mentioned in Apple’s patent). Boron carbide has a density of 2.52 g/cc, so a gold/boron carbide metal matrix composite would have a density of about
A cubic centimeter of this material will contain only
Here, the gold takes up
or 28% of the volume.
Table 1 of Apple’s patent gives other configurations and shows the gold savings.
Some of these numbers look flatly wrong to me. For example, changing from a baseline of 25.8 g of gold in a particular part to 12.1 g is not a savings of 43%, it’s a savings of 53%. Maybe I’m reading the table wrong.
In any event, the patent makes it clear that saving gold is one of the goals of the process. I suppose it’s not surprising that Tim didn’t make a big deal out of that in September.
Maybe Obama will let them rework Fort Knox, if they split with him, of course.
If you want on or off the Mac Ping List, Freepmail me.
Do you really think Obambi has left any gold untouched in Fort Knox?
True. What was I thinking?
This means that the AppleWatch Edition won’t be as expensive as all the Guesstimators, including me, were thinking. I based my estimate on 30grams of 18 Karat gold. . . but if it will only actually take 55% of that amount of real gold in Apple’s Alloy, then the $1000 price for the gold I was assuming is only $550, and that lowers the price. They might be able to see the Edition for around $2000 - $2500 Max.
Won't all that tungsten the Clintons had put in there complicate things?
The basic patent invention is the idea that the pure gold could be mixed with a ceramic such as a Boron Carbide powder and then compressing that very finely ground mixture into a mould under high pressure and then applying heat below the melting temperature of gold to sinter mixture in the mould, solidifying it to form the watch casing.
However, the other claim is that the gold could be also mixed with fine DIAMOND POWDER then sintering that powder mix into the casing mould. Think how hard that watch casing would be. . . and perhaps it would have a very nice glint to the surface. I wonder what black diamond powder would do to the mix?
Apple’s Jonny Ive says the 18k gold in the AppleWatch is twice as hard as normal 18Karat gold. . .
Just when you think they can’t lighten-up anything else, they come up with a way to thin gold. I guess when you can’t work smart and create something good, you create a new way to steal, instead.
Which, by their patents and new techniques, they did
you create a new way to steal, instead.
Is someone being forced to buy this product?
My point is gold was judged by its carat value and is the item solid or merely plated. Then someone figured how to get tungsten in gold bars and coins. Now with this, it’s just something else to have to watch out for. That’s it.
You aren't paying attention. Who said anything about "steal" anything. This is an engineering question. How do you make a watch affordable and still make it out of 18K gold? It will still be 18K gold. . . 75% gold, 25% some other material. This isn't about thinning gold. It's about making it stronger, harder, and lighter. That will keep the cost down, making the AppleWatch more affordable for more people.
The Chinese are selling 9K gold as their approach. It's only 3/8ths real gold.
No, it will still be 18K, and it will still contain 75% gold. Although it is possible to sinter it with Tungsten Carbide to give it the heft of full gold. . . with greater hardness. However, it will not have the color property of full gold under this system. Testing for it will be easy.
Disclaimer: Opinions posted on Free Republic are those of the individual posters and do not necessarily represent the opinion of Free Republic or its management. All materials posted herein are protected by copyright law and the exemption for fair use of copyrighted works.