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Stainless steel certified material test reports do not include a percentage of the pour that came from recycled elements such as iron, chrome, nickel and moly. Do most foundries just buy these on the open market, and do not know what percentage is from recycled stainless?

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John Merrill
Principal Engineer
EagleBurgmann
Matthews NC
7048407045
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As far as I know (European perspective, might differ from US), most stainless steel is recycled. 

It's difficult and not very efficient to produce stainless steel by the traditional blast furnace / converter route and it works much better by the EAF process that uses scrap and ferroalloys as raw material.

So basically, if you're buying stainless steel, even if it comes directly from a producer, it's very often recycled. 
That makes the idea of following the fraction of recycled material a bit moot in my opinion. 

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Veronique Vitry
UMONS
MONS
+32.496.89.71.94
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John,

It should have been disclosed during the audit, unless you are not asking them for scrap addition percent during the audit.

Thanks,

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Sanjay Kulkarni
Materials Engineer
MSSC
2040 Crooks RD, Suite A
Troy, MI 48084
sanjay.kulkarni@msscna.com
Cell: 248-840-1056
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Original Message:
Sent: 10-23-2024 07:23
From: Veronique Vitry
Subject: Recycled Elements Used in New Stainless Steel Production

As far as I know (European perspective, might differ from US), most stainless steel is recycled. 

It's difficult and not very efficient to produce stainless steel by the traditional blast furnace / converter route and it works much better by the EAF process that uses scrap and ferroalloys as raw material.

So basically, if you're buying stainless steel, even if it comes directly from a producer, it's very often recycled. 
That makes the idea of following the fraction of recycled material a bit moot in my opinion. 

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Veronique Vitry
UMONS
MONS
+32.496.89.71.94
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John,

There are no single best practices around melt makeup that every foundry follows.  There are a number of different factors that will go into the melt makeup.  The biggest of these is scrap availability near the foundry.  If there is plentiful scrap of similar chemistry makeup to the needed cast grade, I would expect the recycled content to be high.  If the scrap is not readily available, the recycled content would be much lower.  A chemistry/mechanical property certification generally will not include melt makeup.  If recycled content is required, that would need to be negotiated at time of order and would likely be a separate document listing generic recycled content and not specific to each heat. 

Thanks

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Daniel Baker
Senior Metallurgist
LIFT
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The amount of recycled material would vary from heat to heat, depending on availability of scrap of that particular grade etc.  Worldwide the amount of recycled material used in making stainless is about 60%, but is much higher in the U.S. and Europe.  Individual producers can give you an average for their production.  As the demand for stainless is increasing every year, and it has a very long life in most applications, the availability of stainless scrap is limited.  It is estimated that 95% of all stainless steel is recycled at end-of-life.  Since insufficient stainless scrap is available, producers will use carbon steel scrap for a portion of the heat and add new chromium, nickel and other alloying elements as needed.  Search using recycle at www.ssina.com and at www.worldstainless.org for more information. 

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Gary Coates
Manager, Technical
Nickel Institute
Mississauga ON
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At Cummins, nearly all of our steel, stainless or alloy, is majority made from recycled scrap.

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Steven Ferdon
Director Engineering Technology
Cummins Engine Components
Columbus IN
(812) 344-0276
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I daresay that nearly all alloy systems now regularly incorporate significant percentages of recycled content, exceptions being some tramp elements (eg, cathodic phase formers like Fe, Ni etc in critical Mg and Al alloys). These can degrade corrosion and fatigue performance.  

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James Cotton
Technical Fellow, Retired
N/a,Consultant
Issaquah WA
(425) 223-8060
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