It seems they are referring to a Rockkwell B hardness scale...
February 28 2006, 5:44 PM
Which tops out at 100, in equivalence to a Vickers hardness of 254. That's slightly harder than standard stainless steel, (approx. 220), but quite a bit less than the hardness of some of the heat-treated SS watch cases, (Vickers 1200-1800).
the mechanical properties of ALUSIC are as follows:
very high stiffness, exceptional wear resistance and continual flawless performance even in temperatures up to 300 degrees Celsius or 572 degrees Fahrenheit
Velociphile (Login Velociphile) AP Discussion Group
If the intention was .....
March 3 2006, 5:11 PM
.... to make a very light watch (which I believe it was) then why use AlSiC at all when other lower density materials are available? Yes, Richard must have in mind some other limits that are important to him in order to realise a case, and it would be interesting to undertand his personal limits for these further. Otherwise, why not simply use a polymer for this very extreme application? Ok, so it's hard to justify a 'Casio' case on a high-end watch, but if the intent was partly to keep a 'space/race tech' element to his choice, why not use Aluminium Beryllium ( I think even lighter in the 2.2 g/cm bracket)? What is the real driver to AlSiC? Is there a compelling case for it or is it just to be different?
