Re: Composition of Stainless appliances.

[brian whatcott <inet@INTELLISYS.NET>]

At 07:55 6/6/99 -0400, Chuck Britton wrote:
> ... 'Stainless Steel' is NOT a 'well defined'
> composition. There are MANY different formulations of 'stainless'.
> Some of which ARE ferromagnetic, some are NOT.
...
> I THINK that some 'stainless
> steel' doesn't contain iron at all! (?).
> ...
> Chuck Britton

> > At 20:31 05/06/99 -0600, Ken Fox wrote:
> > > There are new appliances in my neighbors kitchen with stainless front.
> > > ...
> > > magnets do not stick. Is there no soft iron in stainless fronts of these
> > > new appliances?
...

[Mark Sylvester]
> > I rediscovered the fact that stainless steel is not ferromagnetic a few
> > years ago... the tube was made of stainless steel
> > ("inox" in Italian - a good word).



Hmmm. I'm rather doubtful about 'ironless stainless steels.'
There are non-iron stainless metals of course, and some
stainless steels are said to be 'non-steel' on the basis that
their properties (hardness specially) are not improved by
quenching from a hot condition. But then, on this basis,
mild steel, the everyday constituent of structures and mechanisms,
 would not be included as a steel either(!)

   A more pertinent reason for claiming an alloy is not a steel,
 is if the MAJOR proportion of the alloy is not iron, and I am sure
 there are numerous stainless alloys in this category.
(You can see from the chrome and nickel components of one of the
 most popular stainless steels, "18/8", that 26% of that material
is already non-iron.)

Bill in his debunking mode, might well show an interest in the
'stainlessness' of stainless steels.
   In general, none of these alloys is trusted for severe prolonged
underwater service in stagnant brine. (Monel or Naval Bronze are
the prefered materials here.)

   The housewife is doubtless annoyed when she finds that a stainless
 bowl left for a good while with a puddle of water in it, has
developed a pinhole, clear through.

Three major classes of SS alloys are described for their crystalline
structures: Martensitic, Ferritic and Austenitic.Only the last of
these is unconditionally non-magnetic (usually)

Two types with which we tend to be familiar are these:

Cutlery: (Martensitic) hardens to hold an edge, 'stainless'.
 A test with the magnet holding up your whiteware art will confirm
 this is magnetic.

Car trim. (Ferritic) often magnetic.

The third type (Austenitic) forms non magnetic acid resistant, high
temperature or seamless pipe for oil and power industries and I imagine,
beam tubes.
brian whatcott <inet@intellisys.net>
Altus OK