How To Identify An Unknown Casting Spec 1

[tc7]

We did a quick "spark" test on an unknown steel casting with the following result:
Fe 98.32
C 0.38
Mn 0.83
Si 0.18
Cu 0.062
Ni 0.087
Cr 0.0057
Mo 0.034

Hardness is HRB 80.

It seems to compare to a 1040 mild steel.

Can anyone suggest what ASTM or Military material spec for castings may be similar to this. We are looking to weld repair this and want to be sure we have correct electrode and pwht.
Thanks for any help.

 

[arunmrao]

1040 grade of steel is correct,but cast equivalent I have no idea.

 

[metengr]

If you can review ASTM A148 and ASTM A27, and see if you can find a match. ASTM A148 are castings, high strength, for structural purposes.

 

[arunmrao]

ASTM A148 gives only mechanical properties. also the carbon is never maintained this high,also there will be small additions of Ni & Mo in ASTM A148. Hence I did not respond with that spec recommendation..

 

[tc7]

Well I got sort of lucky, I found an ASTM Unified Numbering Handbook (DS-56H) that led me to a Mil-S-22141 specification. That spec has a composition of IC-1040 which comes darn close to my chemical analysis except that my Si =0.18 and Mil-S-22141 analysis calls for Si=.2-1.0; everything else is identical. Additionally this spec calls out a Rockwell B85 max for annealed condition, so I think I have a near perfect match !!!!!!!!!!!!

So then we would normally use a 7018 filler (SMAW) and preheat of 175 deg F, but am not sure if PWHT will be required for annealed condition? Suggestions please?

Thanks again.

 

[metengr]

tc7;
This I can help you with. The preheat for this casting should be increased to 350 deg F, if the thickness is at or above 1". If less than 1", use 300 deg F for the preheat.

The E7018 is fine. I would suggest an H4 low hydrogen electrode. Also, perform either Liquid Penetrant or wet fluorescent MT of the weld and surrounding base metal after PWHT.

PWHT should be specified for this application - 1100-1200 deg F for 1 hour/inch of weld deposit thickness. Over 1" add 15 minutes of PWHT time for each inch of weld deposit thickness.

 

[tc7]

OK Met!!
I'm with you on th PT/MT and the H4. But where do you get the suggested 300 deg F (< 1") preheat?

 

[metengr]

I ran a quick carbon equivalent calc (~0.54), and from prior experience with this material to reduce distortion. I normally like to increase preheat over the minimum specified in literature.

 

[tc7]

Thanks again Met, you're the best!

(can I ask you to stop by thread725-181295 over in Welding,Bonding & Fastening for your thoughts on another Stellite problem, whenever you get a chance?)