From what I've read, the addition of Manganese to stainless steel
increases its wear resistance.  I would like some information in
regards to this increased wear resistance in stainless steel,
preferably quantitative.  I would also like to see a discussion on the
percentage quantity of Manganese in Stainless steel alloys and how the
different levels effect wear resistance and it's impact on other
material characteristics, adverse or otherwise.

Hi stainless-ga.

"Hadfield Manganese Steel 
A specially steel which is austenitic and usually contains
approximately 12% Manganese. It is used in mining, earth- moving
equipment and in railroad track work"
http://www.sfsa.org/sfsa/glossary/deftrmhh.html

"The original austenitic manganese steel, containing about 1.2% C and
12% Mn, was invented by Sir Robert Hadfield in 1882. Hadfield`s steel
was unique in that it combined high toughness and ductility with high
work-hardening capacity and, usually, good resistance to wear."

"Nevertheless, because abrasion resistance tends to increase with
carbon, carbon content higher than the 1.2% midrange of grade A may be
preferred even when ductility is lowered. Carbon content above 1.4% is
seldom used because of the difficulty of obtaining an austenitic
structure sufficiently free of grain, boundary carbides, which are
detrimental to strength and ductility. The effect can also be observed
in 13% Mn steels containing less than 1.4% C because segregation may
result in local variations of ±17% (±0.2%C) from the average carbon
level determined by chemical analysis.

The low carbon content (0.7% C minimum) of grades D and E-1 may be
used to minimize carbide precipitation in heavy castings or in
weldments, and similar low carbon contents are specified for welding
filler metal."
http://www.key-to-steel.com/Articles/Art69.htm

"It is quite true that Mn increases steel toughness if we have in mind
the 13% manganese steel, so-called Hadfield steel. In concentrations
between l% and 5%, however, Mn can produce a variable effect on the
properties of the steel it is alloyed with. The toughness may either
increase or decrease."
http://www.key-to-steel.com/Articles/Art50.htm

"EFFECT OF HEATING
Tempering makes carbon steels more ductile, but Hadfield manganese
steel lose their ductility when tempered. The reason, the austenite is
supersaturated with carbon and manganese atoms that precipitate during
heating. The first transformation is carbide needles in the austenite
grains and after prolonged heating, as a network at the austenite
grain boundaries.(9) They may even form an envelope encasing the
individual austenite grains. The amount of ductility loss or
embrittlement depends on:
1. The amount of carbon. 
A 1.4% carbon steel forms carbides more quickly than 1.0% carbon
steel.
2. The amount of manganese.
Higher manganese decreases the tendency toward carbide precipitation.
3. The temperature and the length of time the metal is held at
temperature.
Heating at 425oC or higher damages manganese steel. Even low-carbon,
high manganese steel heated to 425oC for 48 hours will be embrittled.
4. The rate of cooling after heating within the range between 427oC
and 700oC.
Some carbon will migrate from the austenite during such heating.
Quenching prevents further carbide precipitation, while slow cooling
causes additional loss of carbon to the grain boundaries.

Heating to 650oC substantially reduces the toughness of the metal.
However, there will be more embrittlement if the steel is slowly
cooled and less if it is water-quenched.

At 650oC, the austenite holds only 0.5% carbon in solution and at
900oC, it dissolves 1.0% carbon. Fig. F-4. A 1% carbon steel heated to
900oC and then quenched would have no free carbides, but a steel
containing 1.4% carbon given the same treatment would have 0.4% carbon
in excess of the amount soluble in the austenite. This excess carbon
would be present in the form of carbides"
http://www.maxpages.com/msper2000/A2_Solution

"Manganese steel (also known as Hadfield managanese steel) contains
about 12 per cent manganese and from 0.8 to 1.25 per cent carbon. If
there is only 1.5 per cent manganese, the steel is very brittle, and
additional manganese increases this brittleness until the quantity has
reached 4 to 5.5 per cent, when the steel can be pulverized under the
hammer. With a further increase of manganese, the steel becomes
ductile and very hard, these qualities being at there highest degree
when the manganese content is 12 per cent. The ductility of the steel
is brought out by sudden cooling, the process being opposite that
employed for carbon steel"
http://www.zianet.com/ebear/metal/heattreat7.html

Is that the kind of info you require?

Hope it helps

Dr_Know

Hi there,

Thanks for your response.  You are on the right track.  I read through
the information you sent me several times and compiled some comments.

My questions were as follows:
1. I would like some information in 
regards to this increased wear resistance in stainless steel, 
preferably quantitative.
2. I would also like to see a discussion on the 
percentage quantity of Manganese in Stainless steel alloys and how the
different levels effect wear resistance and it's impact on other 
material characteristics, adverse or otherwise.

First of all, it is unclear to me that these reference are refering to
stainless steel.  I'm not sure if Hadfield Manganese Steel fall in the
stainless steel category.  Stainless steel I think is designated by
the existance of Chromium and Nickel in the steel alloy to help
mitigate corrosion.  Do the facts you provided apply to stainless
steel?  The following comments assumes the answer to this questions is
yes.

Your paragraph:
____________________________________________________________________
"The original austenitic manganese steel, containing about 1.2% C and
12% Mn, was invented by Sir Robert Hadfield in 1882. Hadfield`s steel
was unique in that it combined high toughness and ductility with high
work-hardening capacity and, usually, good resistance to wear."
_____________________________________________________________________

This is exactly the type of information that I want and addresses
question #1.  I would like to know more information about the high
toughness and ductility and resistance to wear.  I would really like
to know some quantitative information so I could compare steel with
Manganese to stainless steel without Manganese.  If I have 12% Mn in
steel, will it be 3 times as wear resistant the other steels without?

Your paragraph:
____________________________________________________________________________
"It is quite true that Mn increases steel toughness if we have in mind
the 13% manganese steel, so-called Hadfield steel. In concentrations
between l% and 5%, however, Mn can produce a variable effect on the
properties of the steel it is alloyed with. The toughness may either
increase or decrease."
http://www.key-to-steel.com/Articles/Art50.htm 
_____________________________________________________________________________

This is also the type of info I need.  It addresses question #2.  More
detail on this would be helpful.  I haven't check the link out.

So far I know the following:
1.  The types of benefits I could expect from having Mn added to an
alloy.
2.  How having different percentages of Mn effect the material.

What I don't know is:
1.  How much of a benefit do I get from adding Mn compared to other
materials.
2.  What are the negative properties of having Mn other then too low a
percentage.  Is there any reason why I wouldn't want Mn in my
material.?
3.  Does all this information apply to stainless steel?

Matt

Your asking a very broad question about two very broad topice
(stainless steel % triboligy).
you asked:
1.  How much of a benefit do I get from adding Mn compared to other
materials.
             What other materials???
2.  What are the negative properties of having Mn other then too low a
percentage.  Is there any reason why I wouldn't want Mn in my
material.?
          The amount of preferred Mn in your material will be dictated
by the material application, but yes too much Mn in your S/S will be
counter-productive.

3.  Does all this information apply to stainless steel?
            It is better not to confuse stainless with carbon steel as
the effects of certain elements will obviously be not be the same due
the different chemistries.

I recommend you seek out "Review of the wear and galling
characteristics of stainless steels", Committe of stainless steel
producers, American iron and steel institute, Apr 1978