Omelet wrote:
> Dave Smith > wrote:
>> George wrote:
>
>> > In the case of S/S it is the nickle which makes it non-magnetic. S/S
>> > that contains both chromium and nickle is called "austenitic" or
>> > commonly known as 300 series. 300 series alloys that have low amounts of
>> > nickle can become magnetized.
>
>> Curiously, nickel is magnetic. However, when it is added to steel the
>> crystals are formed in a way that makes the product non-magnetic.
>
> So magnetism is a property of metallic structure and not elemental
> content?

Magnetic retention is a function of the element combine with the crystal
structure. Because magnets have poles even on the scale of atoms it's
possible to form crystals where the poles line up to make the object
more magnetic and it's possible to form crystals where the poles go
opposite to make an object that is nearly non-magnetic.

Crystal structure is microscopic, metallic structure is macroscopic.
Metals are made of lots of crystals put together. If a crystal can
shift its pole to line up with other poles then the ramdom crystals in
the metal is magnetic. If a crystal can't shift its pol to line up then
the fact that there are a lot of randomly oriented crystals keep the
metal non-magnetic.

If you've ever worked with sugar to manipulate its many types of
crystals to make hard candy versus fudge you know how complex and
technical it can be. Metalurgy with iron/steel has the exact same set
of issues.

For that matter chocolate is temperer to make it stronger using
temperature sequences in a way that very much reminds me of tempering
steel by using temperature sequences. Both sugar and steel are made of
a single material (iron or glucose/fructose) that can have many
different crystal structures and so both can be manipulated with skill.

A highly skilled candy maker and a highly skilled steel smith could
learn each other's dictionary of technical terms and crcoss train in
each other's skill with less effort than you might expect.

When I watch Challenge on FoodTV I often watch the candy specialists
temper chocolate and/or sugar and wonder what sort of mixtures they
could use to make their sculptures stronger and less brittle. With
steel it's done by making the metal soft on the inside and hard on the
outside with a quick quench to drop the temperature and freeze the
crystal structure. Making candy sculptures is very similar in principle
to making buildings or bridges.