odd steel bar identification

[Screwdriver]

i know that but i thought things like duplex had no iron in it but was still called stainless steel

No idea, I only just heard of the stuff but google knows all: http://www.imoa.info/molybdenum-uses/molybdenum-grade-stainless-steels/duplex-stainless-steel.php

And if it's got steel in it, it is ferrous. Magnetic or not

S.

 

[BrokenBiker]

so what about austenitic stainless then? im sure there are some grades of stainless that have no iron content at all. i can remember being told about them in college as part of our properties of material course

 

[Maker]

so what about austenitic stainless then? im sure there are some grades of stainless that have no iron content at all. i can remember being told about them in college as part of our properties of material course

That wouldn't be stainless steel then. Were they talking about inconel/monel (nickel alloy)?

 

[BrokenBiker]

That wouldn't be stainless steel then. Were they talking about inconel/monel (nickel alloy)?

could have been...as an electrician i wasnt really sure why i had to deal with a properties of materials class...it wasnt on my course list, my employer didnt understand why i was doing it but the college wouldnt let us avoid it so i just winged it to be fair

 

[TechnicAl]

Steel and Stainless Steel contains Iron so it is a Ferrous metal

To make steel Stainless you have to add 12% Chromium

To make it more Stainless you can add 17% Chromium

These steels have a Ferritic Structure (microscopic)

!7% Cr steel is stainless but its not very malleable so someone added 8% Nickel

17Cr 8Ni steel is Austenitic.........still ferrous but not ferritic

Ferritic Stainless attracts a magnet, Austenitic doesnt

 

[Maker]

Steel and Stainless Steel contains Iron so it is a Ferrous metal

To make steel Stainless you have to add 12% Chromium

To make it more Stainless you can add 17% Chromium

These steels have a Ferritic Structure (microscopic)

!7% Cr steel is stainless but its not very malleable so someone added 8% Nickel

17Cr 8Ni steel is Austenitic.........still ferrous but not ferritic

Ferritic Stainless attracts a magnet, Austenitic doesnt

How does martenistic (sp) come into it? Does it contain manganese?

 

[TechnicAl]

How does martenistic (sp) come into it? Does it contain manganese?

Basically if you add Carbon to the 17% Cr steel it will change from Ferritic to Martensitic
They nearly all contain Manganese at relatively low levels

However, there is a steel that contains 14% Manganese (sometimes called Hatfield Manganese steel) which is austenitic (another way of doing it) but its not as malleable as the CrNi or the Ni Base austenitics.

 

[TechnicAl]

This will help with understanding stainless

some elements form Ferrite (Chromium Equivalent) others for Austenite (Nickel Equivalent) their potential is expressed as a multiplier

add them together for each group and where the lines cross is the structure

This assumes that if its possible it will happen which isnt always true so there are exceptions

 

[Rrunnach]

Sound like a job for my Clandon Metascope.

 

[TechnicAl]

Sound like a job for my Clandon Metascope.

Needs to be accurate

 

[Rrunnach]

No idea of accuracy, I still have sample box, couple of samples are missing, I should really punt it on eBay.

 

[TechnicAl]

as far as I recall they were termed qualitative rather than quantative
ie they could differentiate if there was enough difference

The XRF machines used to PMI these days are much more accurate

 

[Kent]

Tried a spark test? might tell you something might not but hey there you go when you buy unknown stuff

 

[Rrunnach]

as far as I recall they were termed qualitative rather than quantative
ie they could differentiate if there was enough difference

The XRF machines used to PMI these days are much more accurate

I imagine PMI equipment has changed for the better with new technology. I also have (some bits missing, lens I think) camera that would attached to viewing port, where you could actually take an image of colour spectrum. All the kit is probably a museum piece now, I doubt companies use MetaScope gear, now?

 

[TechnicAl]

Its basically a measured spark test.........every colour represents a different element so the spectrum can be measured and compared against known samples. In the day they were good.............better than taking drillings and dissolving for a few days in acids etc etc

 

[Rrunnach]

Its basically a measured spark test.........every colour represents a different element so the spectrum can be measured and compared against known samples. In the day they were good.............better than taking drillings and dissolving for a few days in acids etc etc

You could say measured spark was 1st generation bar code, I found this link to instructions, I'm a tad miffed I misplaced Olympus camera lens, as everything else is there!!

https://www.dropbox.com/s/fyeyydbpxsu9opn/metascope1.pdf