×
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!
  • Students Click Here

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Students Click Here

Jobs

Subjecting 307 (18-8-6 Cr-Ni-Mn) to extensive preheat?

Subjecting 307 (18-8-6 Cr-Ni-Mn) to extensive preheat?

Subjecting 307 (18-8-6 Cr-Ni-Mn) to extensive preheat?

(OP)
Is there a detrimental effect on weld deposit of stainless steel type 307, when it is subjected to preheat of 350°C = 660°F for 1h?

We've got high carbon steel (CEv = 1) that was surfaced with 13% Mn FCAW years ago. Now the piece needs resurfacing.
This steel needs preheat of 350°C, whereas the Mn layer cannot withstand 200°C (due to carbide precipition).

As you cannot tell what parts or what depth has been resurfaced with the Mn wire, I would suggest preheating to 350°C, then a butter layer of 307, then resurfacing with hardfacing rods 350HB.
This would mean that the 307 would be subjected to high temps for quite some time (30 minutes to 1 hour, the duration of the welding operation).

Any thoughts on the use of 307 as a butter layer at these temps?


For your information, the workpiece is a switch crossing of little importance made from rail steel.

RE: Subjecting 307 (18-8-6 Cr-Ni-Mn) to extensive preheat?

you are talking about 218 stainless? Anything with 8% Mn is not a 3xx alloy.
You are looking to use this a weld overlay on steel, correct?
E307 weld filler is only 4%Mn, 20Cr, 9Ni.
If your filler is low C (not more than 0.03%) and you don't have a lot of dilution then the overlay should not sensitize significantly at 660F.
But I don't see why you don't directly apply the hardfacing?

= = = = = = = = = = = = = = = = = = = =
P.E. Metallurgy, Plymouth Tube

RE: Subjecting 307 (18-8-6 Cr-Ni-Mn) to extensive preheat?

(OP)
Ed, thx for your response.

google for AISI 307: you'll find most suppliers have a composition of 18 (or 19)% Cr - 8 (or 9) % Ni - about 6% Mn (At least in Europe, we do).

Yes, this is weld overlay. Problem is that the underlying surface is possibly (or highly likely, depending on the exact location) Hadfield or 13% Mn steel.
This cracks and fissures enormously when heated. Hence a ductile butter layer (elongation = more than 35%) to stop the underlying cracks from mounting upto the surface, causing more chipping/spalling.

The hardfacing rods we're currently using have 0.10%C.

RE: Subjecting 307 (18-8-6 Cr-Ni-Mn) to extensive preheat?

There is a UNS designation W30710, that is what I referred to.
It sounds like you are stuck.
I am guessing that they ignored perheat (or used a much lower temp) when they overlayed the Hadfield.
Grinding it off is your only real option, since you obviously don't want to start over on a new part.

= = = = = = = = = = = = = = = = = = = =
P.E. Metallurgy, Plymouth Tube

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members!


Resources