Does anyone know how to weld the cast alloy with 1.7%C, 56%Fe, 34%Ni, 4%Cr, 3.5%Si, .37P? And what type of alloy is it?
I don`t have the Schaeffler diagram on hand at the moment, but due to the high nickel and carbon content, I`d say that it`s a fully austenitic alloy.
Does it have a brand name? Do you know who`s the manufacturer?
Giovanni S. Crisi
Sao Paulo - Brazil
Dear Dmitriy,
I've received your e-mail but I prefer to put my answer on the AWS Forum, so it'll be read by many people and corrected if it's wrong.
My advices are two:
1st. You say that the material belongs to a GE turbine. So, my first advice is that you ask for GE's recommendation on how to weld a material that makes part of a machine they've sold.
2nd. Some time ago I've read quite a few comments on this Forum on how to weld turbine blades and other parts. My second suggestion is that you read those comments. Click on the word "Search" on the upper right corner of this image, then write, say, 730 (2 years) where it says "Maximum post age", 100 where it says "Limit posts" (100 is the maximum) and "Turbine blade welding" where it says "Keywords".
Tell me how did you come along. Good luck
Giovanni S. Crisi
OK, let's stop and think about this. "1.7%C" sounds like a cast iron and Ni and Cr suggest mabe a NiHard or NiResist grade off the top of my head. And 0.37%P is a bit on the high side for weldability. If these chemistry values are not typos, then a NiRod 55 or NiRod 99 would seem to be likely choices for SMAW electrodes. Not sure about preheat, 500-600 F?
The GE thing kind of rings a bell. I have some data at another location from a different turbine manufacturer about a cast iron alloy that has a low CTE. Mr. Simms reccomendations seem in line, but you also might explore Invar type filler metal. I'll try and remember to look up the info at work tomorrow and see if the composition is similar. The Cr and Si seem a little higher than what I was looking at though. Could just be a difference between the manufacturers.
Mr. Roberts,
English being not my mother language, I don't understand what do you mean by "GE thing kind of rings a bell". Is that a good thing or a bad thing?
I don't know also what stands for "CTE".
Would you be so kind to clear them up for me? Thankyou.
Giovanni S. Crisi
Prof. Crisi,
When someone says ........"rings a bell", that means that the subject is vaguely remembered. Say, if in conversation someone asks you if you know a guy by the name of John Doe, you'd say, "that name rings a bell" if you think you have heard that name before but not 100% certain. All it means is that you might have possibly met the guy, and you think you have, but not quite sure. The phrase can apply to anything on those lines.
As for CTE, I don't know.
Tito
Thanks, Tito. From what you said, I understand that what Mr. Roberts meant is that GE is not 100% available to give aftersales technical assistance on the machines they sell.
What a surprise! I've always had a great respect for GE.
Giovanni S. Crisi
Prof. Crisi,
I'm not convinced that that was what he was meaning, as far as the availability of GE. I think he meant that with the subject at hand that he may have dealt with a GE turbine for a similar subject, but he's not quite possitive of it. He may have, and thinks he may have, but he may not have.
Does that make any sense, because I think I'm starting to confuse myself.
Tito
Mr. Crisi,
Sorry if I am a bit confusing. When I said that "GE rings a bell", I meant that it reminded me of some turine work done previously. Nothing related to the performance of GE as a company.
CTE = Coefficient of Thermal Expansion
John Wright
I learn something new everyday.
Tito
As I know, Grey cast irons cannot be welded because of the graphite flakes. Some experiments on Grey cast iron welding have been done according to ASME IX and the results are not satisfactory because the HAZs are too weak. But nodular cast irion is feasible to be welded by ENi-CI filler metal. But I cann't tell which type of cast iron the one you mentioned is.
Thanks a lot. I'm very pleased that some of us have learned something new (And I am too).
First my futile attempt was when I used ENi-CI (similar to NiRod 55). I got a lot of cracks in all directions. So, I've just tried to weld it by ENiFe-CI ( C=1.2; Fe=45; Ni=bal). The final result is the same. I think the combination of elements (4%Cr , 1.7%C and 0.35%P) is critical for hot cracks appearance. Does anyone has experience to weld any alloys with 0.35 or >%P?
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