Welding stainless to nickel

By - Date 04-21-2005 13:08

Good Morning,
I would suggest using an ENiCrMo-3 (625). You can reference this recommendation in ANSI/AWS A5.11/A5.11M-97. But, let's look at the options.
A 309 is not recommended because it is used to join stainless steels to a carbon steel, or dissimilar stainless steels to each other. Although the 309 will weld to both, it is not recommended because it will greatly compormise the strength of the nickel alloy.
A pure nickel rod (ENi-1) is not recommended because it is not a stainless filler metal. To be a stainless metal, it must contain approximately 11% chromium. Using this as a filler will compromise the corrosion resistance from the 304 and have a much greater chance of hot cracking.
Using the ENiCrMo-3 [625 (60Ni-22Cr-9Mo-5Fe-3.5Nb plus Ta)] will continue to give the strength of the Ni plate and the overalloying of the Cr to match the 304 stainless.

Chuck

By cmansonite (*)

Date 04-21-2005 13:29

Thank you much, Chuck.

By GRoberts (***)

Date 04-22-2005 01:24

Mr. Meadows:

I am wondering what you mean by "it is not recommended because it will greatly compormise the strength of the nickel alloy."

Since the fellow will be welding to 304 to nickel, as long as the weld is at least as strong as the weakest member, the weld would be adequate according to ASME IX. Also, Typical mechnical properties for Nickel 200 (99.6% pure Ni according Inco alloy catalog) is 67ksi tensile, and 21.5ksi yeild, and for Nickel 201 (99.6% Ni, with low carbon) is 58.5ksi tensile, and 15ksi yeild. However, ASTM A240 stainless steel plate type 304 has a 75ksi minimum tensile and 30ksi minimum yeild. Also, AWS A5.4 specifies a minimum tensile for E309-xx of 80ksi, and a minimum yield of 30ksi. So I don't see how 309 would compromise the strength of either material.

I am also wondering why nickel rod would not be appropriate due to it not being "stainless". Since the plate being welded to is nickel, and assumed to be satisfactory for that environment, would a nickel weld also not be suitable for the environment?

cmansonite:
With any of the filler metals mentioned thus far, you will end up with a fully austenitic deposit, whether you use 309, NiCrMo-3, or ENi-1. So you will have to use techiques for welding nickel alloys to avoid hot cracking, but it is not hard if the guidelines are followed. If I were you I would either try 309, or NiCrFe-3 (or NiCr-3 for GTAW), which would be an economical Nickel alloy that matches the strength of both metals farily well, instead of being overmatched, which will only add to distortion.

By - Date 04-22-2005 12:41

I recommended a nickel based alloy because of the amount of nickel and chrome. A 309 contains only 12-14% nickel. A 304 base metal contains approximately 8% nickel. Without knowing all the facts as to why the pure nickel was selected, probably for high temp service, I felt and still feel the nickel alloy is suitable. I think that "as long as the weld is as strong as the weakest member" is not the driving force here. I think trying to match the strength and alloys of the higher alloy is equally, or more important using this scenario. May I give an example here? If you are welding a 2205 Duplex material to a 304 stainless, would you use a 308L filler metal with a 75K tensile, or would you use a 2209 filler metal with the 100K tensile that matches the 2205 base metal? I've been taught by people a lot smarter than me to try to match the highest grade in virtually all the cases. Sometimes you need to look beyond just the tensile and yield to consider what long term effects will be compromised in different environments and temperatures. We are all entitled to our individual recommendations in this formum, and I certainly respect your comments, and as you indicated, we are also entitled to agree or disagree with another's recommendation. It so happens that in this case, I personally would not recommend a 309. I did not recommend the ENiCrFe-3, as you did, because of the lack of molybdenum, which would help provide corrosion protection. When I mentioned "compromising the strength", I was not necessarily speaking of the weld in it's present condition. I was looking at possible sigma formation and time at temperature in the environment I supposed it was to be placed in. Again, I did not read what service and temperature it was going to be in, so maybe I assumed too much. I spoke to 2 other fellow Welding Engineers, as myself, and they both agreed that a nickel based material is a good recommendation in this case. I think we should make our recommendations, state our reasons for making those recommendations, and let the author make his decision that he feels best suits his needs. Mr. Roberts, thank you for your comments as they are well taken.

Chuck

By - Date 04-22-2005 14:35

Mr. Roberts,
If I may, I am wonderiing why your statement,"If I were you I would try 309 or ENiCrFe-3 (or NiCr-3 for GTAW) which would be an economical alloy that matches the strength of both metals fairly well, instead of being overmatched, which will only add to distortion." Regarding the economical aspect, the NiCrFe-3 contains 5% more nickel than the NiCrMo-3. Agreed that the NiCrMo-3 contains more moly than the NiCrFe-3. Please allow me to say that the surcharge of nickel is higher than the surcharge for moly. Therefore, the NiCrFe-3, with the higher nickel content is not more economical. Both the NiCrFe-3 and the NiCrMo-3 are "overmatched" only to the 304. They both contain considerably less nickel than the nickel base metal, which could be considered undermatched. Using the NiCrMo-3 will cause no more distrotion than if he used the NiCrFe-3.

CM

By GRoberts (***)

Date 04-22-2005 15:26

Right now we are paying close to $50/lb for pure moly, while nickel we have been getting under $10/lb. We usually end up buying NiCrFe-3 for about $10/lb and NiCrMo-3 for $12-14/lb. Although compared to the base metal cost and labor cost, the filler metal cost will not be that significant. The best thing to do is to choose the best filler for the situation. I mention distortion, because the stronger the filler metal, the more force it can exert on the base metal as it cools, thus more distortion-which when welding butt joints on thin stainless/nickel, can be a problem. Also, as I pointed out, 309 filler metal will be as strong or stronger than both base materials. I do enjoy the lively debate, and it is good to get different ideas out there.

By - Date 04-22-2005 15:34

Mr. Roberts,
Please do not take these replies to your comments to me as being argumentative, but I think we need to clarify some things so that our author can make a decision based on all that has been presented to him. If distortion is a concern to the author, we need to give very accurate information. Very respectfully, allow me to give some data taken directly out of our Avesta Welding Manual, Practices and Products for Stainless Steel Welding. Can we agree that distortion is caused by heat input and interpass temperatures? I would.
Using the SMAW welding technique, and assuming he is using a 1/8" diameter welding rod, let's look at the heat inputs and interpass temperatures for both the 309 and the 2 nickel alloys we both presented (NiCrFe-3 and NiCrMo-3). This is directly out of our catalog.
The recommended Current (Amps) for the 1/8" 309 is between 80-120 Amps, with an interpass temperature of 150C.
The recommended Current, (Amps) for the 1/8" NiCrFe-3 and the NiCrMo-3 is between 60-95 Amps, with an interpass temperature of 100C.
Naturally, the nickel is welded at a lower heat range due to the austenitic structure, or lack of ferrite, so as not to encounter the greater possibility of hot cracking, which you and I both agree. Using "properly recommended" welding practices, one can actually cause more distortion using the 309 than the nickel alloys. Thank you.

CM

By GRoberts (***)

Date 04-22-2005 19:29

I agree that preheat and heat input relate to distortion, and your data may be right, but some of your conclusions are not. I'm also not trying to argue, just to get the best information out there for all.

1st, preheat is used to help reduce distortion. The higher the preheat, the lower the overall distorion will be after welding. Therfore, if distortion is the main concern (and is may not be in this particular case), the least distortion would be encountered by the process that allowed the highest preheat. In this case, that would be the 309.

2nd, heat input and amperage are not the same thing. Heat input (kJ/inch) is amps X volts X 60 devided by travel speed (inches/minute), So if you have a higher travel speed with the E309, you can have the same or lower heat input as when using ENiCrFe-3 even if you are welding at higher amperages. So the heat input would be operator dependant, based on travel speed. As a general rule, all else being the same (such as process, rod size, etc), if you deposit the same size bead, your heat input will be the same regardless of your amperage, since amps and travel speed have the opposite affects on bead size. So I don't think the amperage range has a direct affect on distortion.

But let's face it, on thin material, fixturing, welding sequence, and avoiding excessive heat input will do a lot more to help control distortion than what type of filler metal they use. However, filler metal type leads to good discussions.

By - Date 04-22-2005 20:12

OK, lets talk about this. First of all preheat is not recommended for welding stainless other than to remove moisture. When welding stainless steel, preheat is not used to reduce distortion. Depending on what you consider "high" preheat, the preheat can actually alter the phase balance of a 309. This exact subject (Grain Growth in Stainless Steel Heat Affected Zones) is the subject of a paper I'm presenting at the AWS Conference in Dallas next week.
Next, I'm very aware of how to calculate heat input. I've been doing this for over 30 years. I hope you're not trying to tell me that if you are running a 1/8" diameter welding rod at 75 Amps, you will be putting the same amount of heat into the base metal as if you were welding at 100 Amps, because it is not true. When welding stainless steel, distortion can be controlled in many other ways than by a high preheat, or any preheat for that matter. Preheating a stainless steel destroys the chromium layer on the surface that is used for corrosion protection. Even though you said you don't agree, I can assure you that a high amperage welding process is going to cause more distortion and increase grain growth is the HAZ of stainless steel, and neither are good. If you are going to the AWS Conference next week, I will gladly share with you my Power Point presentation and that will answer a lot of these questions, or uncertainties. Lastly, preheating of carbon steel is acceptable for reducing distortion, but not for stainless steel.

CM

By - Date 04-22-2005 20:50

Mr. Roberts,
Please allow me to quote from a presentation being presented next week at the AWS conference regarding preheating of austenitic stainless steels (309 in this case). "It is not normally necessary to preheat austenitic and duplex stainless steels. Provided, of course, that there is no condensation on the steel, these grades are usually welded from room temperatures (i.e. ~20C). Where there is condensation, the joint and adjacent areas should be heated uniformly and gently (i.e. not so hot that they cannot be touched). Local heating above 100C must be avoided as it can give rise to carbon pick-up or metallurgical instability. Both of these have a negative effect on the steels' properties". Hopefully, this will help you change your recommendation about a high heat preheat of a 309, or a 304 base metal. I can guarantee you that using a high preheat to help reduce distortion will lead to much more severe problems than just distortion. I.E., loss of corrosion protection, lessen the strength of the steel, alter the phase balance, and deplete the chromium enriched area that the preheat is applied to, just to name a few. Again lastly, even in carbon steel, a preheat is not done for the filler metal, but to relax the molecules of the base metal before welding ever starts.

By GRoberts (***)

Date 04-22-2005 23:34

Mr. Meadows,
I was not recommending preheat on stainless steels, I was just talking about the general principals of distortion control. Sorry if you though I was saying that. Since we are talking about distortion control, I guess I am not understanding why you listed the maximum interpass temperature in your earlier post about distortion control- I thought (wrongly) you might be making an inferenace to preheat by that?

All I am saying about the heat input, is that if you put in the same size bead with a weld at 100 amps, and one at 75 amps (which would mean you have to travel faster), you will be putting the same heat into the base metal. The one with 100 amps will just get the weld done faster. I wouldn't exactly call 100 amps for SMAW a high amperage process though, as far as stainless is concerned.

Anyhow, I hope you have a great trip to the welding show. I made it last year, but this year is a little too hectic.

By - Date 04-23-2005 01:30

Mr. Roberts,
I do not want to get into a "war of words", but in your previous response you specifically mentioned allowing the highest preheat temperature to avoid , or reduce, distortion of the 309. In fact, the preheat, which is not even recommended, would be for the base material (304), not the filler metal (309). When we are speaking of "generalities" we must distiguish between, in this case, stainless and carbon steels. This author was concerned with stainless and nickel alloys, not carbon steels. I thought, maybe I was not clear, that I was referring to heat input and interpass temperatures as two seperate intities. I understand what you're saying about putting the same size weld bead on a base metal, but it is unlikely that using 75 Amps to deposit a weld bead will be the same travel speed if you are using 100 amps. The lower amps requires a slower travel speed normally. I did not intend to say that 100 amps is high for welding stainless steel. For a 3/32" diameter stainless steel welding rod, regardless of the alloy, I would consider that a high amperage. But, for a 5/32" diameter stainless welding rod, regardless of the alloy, I would consider that a low amperage. I was merely using the 1/8" diameter as an example. Naturally, the amperage is going to be dependent on the welding rod diameter and the thickness of the part being welded. At some point, if needed, I would gladly share with you a paper presented at the latest NACE (National Association of Corrosion Engineers) in which I am a Member in Good Standings, regarding this very subject we are discussing. It ties directly into the paper being presented at the AWS conference next week about avoiding preheating stainless steels. Unfortunately, the "principals of distortion" do not allpy to stainless steels as they do to carbon steels. As I said earlier, I appreciate, as do all our readers, the comments and recommendations we all post on these forums. Discussions such as you and I are having only better educate the persons that do not deal in stainless steel as much as we do. Personally, as a Welding Engineer, I have specialized in stainless steel and the welding of stainless steel for over 30 years. I do not mean to imply that I know it all, I don't, but I can provide documented data to back up every comment I make on these forums.
My trip to the welding show will be a short one since I live in Dallas anyway. I would be happy to communicate with you outside of this forum if you so desire. I have a lot of data pertaining to stainless steel in my library is you want more information. Again, thank you for your comments.

Chuck

By - Date 04-23-2005 16:35

Mr. Roberts,
First of all, let me say how much I enjoyed our communication over the past couple of days. Also let me say that if I ever said or indicated anything less than with the most respect and gratitude, I sincerely apologize. I truly mean that. If mentioning that I'm a Welding Engineer (that is not my job title, but my chosen field) or that I belong to NACE, or am presenting a paper at AWS, if any of that offended you or made you feel uncomfortable, I also apologize for that, too. Personally, I enjoy getting to know the people in these forums, their background, their experience, chosen fields, etc. This is not to try to judge them, but to get to know them and make these forums a little more personal. If that is wrong, so be it. Apparently MBSims feels that a warning flag should be thrown up when people share this information, so I will be very careful not to share things like that in the future. I'm sure that there are some that share his feelings, but I'm sure there are those that do not. However, the purpose of these forums are to share information, whether it is on a personal basis or strictly recommendation-wise. Not all of these forums are going to please everyone, and that is the beauty of this scenario. Sharing... Again, if I, even in the slightest, offended or said anything to offend you, I'm sorry. I hope we can continue to share our thoughts even if they don't always go hand-in-hand with each other.

Chuck

By GRoberts (***)

Date 04-25-2005 00:08

Mr. Meadows,
No offence here. Just because I don't always agree with someone doesn't mean they offend me. It seems like were good as mis-communicating as well as disagreeing on some things, but that's what makes the board interesting I suppose. I personally agree with MBsims, but I also try to allow for people with different opinions and personalities, so I know that there will be people that don't.

I hope your presentations go well.

By MBSims

Date 04-23-2005 14:36

"Can we agree that distortion is caused by heat input and interpass temperatures?"

Distortion is primarily a function of joint restraint, weld deposit contraction and weld joint geometry. Heat input and interpass temperature also have a role in controlling distortion, but to a lesser degree. I once welded two 304L test coupons, one with 3/32" electrode and the other with 5/32" electrode. The joint welded with 5/32" electrode with a few large weld beads and higher heat input underwent less angular distortion and weld shrinkage than the one welded with 3/32" electrodes with many small beads and lower heat input per bead. When we want to minimize distortion on welds in the field, we always weld with a large electrode and as few passes as needed to finish the weld.

Either of the electrodes that were suggested are acceptable, for the many reasons cited by CMeadows and Groberts. The 309 is more readily available than the nickel alloys if procured at the local welding suplly house, although the NiCrFe-3 can be ordered. My experience has been that the ENiCrFe-3 is definitely more expensive than E309L-16. Given the information that was available, I would have assumed that at the weld location if 304 base material was acceptable for the temperature and corrosion conditions, then 309 weld metal would also be. I note that the Nickel Development Institute literature recommends ENi-1, ENiCrFe-3 or ENiCrFe-2 for welding Nickel 200 or 201 to 300 series stainless steels.

http://www.nickelinstitute.org/multimedia/technical_support/technical_literature_pdfs/11000_reference_book_series/11012.pdf

I can say all this comfortably without stating how many years of experience I have or what my title and position are. One of the features I liked about this forum in the past was the great communication between folks that weld in the field every day, experienced welding and metallurgical engineers, and acedemia. I can't recall any of them basing the validity of their answers on how many years of experience they had or what company they worked for. Quite honestly, when I encounter people who do that in my daily job it usually sends up a warning flag that something may not be kosher, so some caution is advised about how often you do that.

By GRoberts (***)

Date 04-25-2005 00:15

MBsims,
Thanks for your valuable comments. I would agree with them 100%. I was originally taught by one of my professors that larger passes of the same volume will produce less distortion than small passes, and have experienced the same thing myself, but didn't mention it because I don't have any good references. People look at you strange when you say that because they are used to larger passes having greater distortion due to the larger volume of weld metal deposited. The key of course is not to deposit more metal with the larger passes.

By jwright650 (*****)

Date 04-21-2005 15:04

[Quote]PS: Harley, just the link please, no 5 page salespitch. Thank you.[/Quote]

:) <snickering>
John Wright

By harleyhitman (**)

Date 04-22-2005 01:00

you don't know how tempted I was to cut and paste the 5 pages !

Here's 2 links to the best products on the market !

http://webapp1.cronatronwelding.com/cronatron/showLevel4?productClassNum=02080100

http://webapp1.cronatronwelding.com/cronatron/showLevel4?productClassNum=02080200

By - Date 04-23-2005 15:46

MBSims points are well taken, but doen not necessarily reflect the feelings of everyone in these forums. His comments about stating one's education, experience, job title, employment company, etc. not being "kosher" is certainly his opinion. These "un-kosher" attributes can tend to lend credibility to some of our answers when there is more than one recommendation. Whether one cares to reveal their company, job title, experience, education, etc. should be up to the individual. If one chooses not to share his experience, job title, etc. is also his choice, but to say that when one does choose to share these things that it "throws up a red flag" is a bit much. I guess the same thing could be said about a person that chooses not to share that information. I would hope that anyone MBSims might possibly be referring to would be able to provide documentation on any of the things he finds to be in doubt, like education, experience, job title, company, etc., if he feels there is any falsification going on in here. Of course, that can go both ways. In closing, a recommendation of filler metals are strictly that, a recommendation. Without knowing all the variables the weld is going to encounter, sometimes a recommendation can be misleading or maybe even wrong. This is not saying that is the case in this instance, but none of the pertinent information was given by the author, so all of our recommendations were valid. Because one manufacturer, or entity, recommends one thing and another recommends another does not take away credibility from either. Mr. Sims, I just hope you are not quick to judge someone that you don't know or have no association with. Thank you.

CM

By Jim Hughes (***)

Date 04-25-2005 22:54

Amen Chuck. When are you going to be in Seattle? I still would like to make to one of your conf. I have some S.S samples I would like you to look at.
Jim Hughes

By - Date 04-26-2005 01:12

Jim !!!! Where ya been my friend? I just talked t the people in Seattle and things are still on go, but no firm date is set. Hope the stainless steel information I sent you is serving you well. These forums were getting a little spirited, huh??? >smile>Chuck

By - Date 04-28-2005 14:49

Jim,
I met with the people from OxArc in Spokane, Wa. at the AWS Show and my Stainless Steel presentation is scheduled for September there in Spokane. I will let you know the exact dates when that part is finalized.

Chuck

By MBSims

Date 04-26-2005 01:34

Chuck,

I agree, my comments were my own opinion. Just offering a word of caution based on my own experience with dealing with contractors and vendors. I would not judge anyone that I have not dealt with directly and even then would take time to know them. If someone offered me an opinion and said it was based on a similar experience, testing they conducted or were familiar with, discussions with industry experts, a successful project, or an unsuccessful experience, I would have a lot more confidence in the response. I think it's great that we have a representative from a major electrode and filler metal manufacturer participating in the AWS forums.

By - Date 04-26-2005 11:54

Mr. Sims,
I can understand your caution under certain conditions, but at the risk of offending you (maybe a bad choice of words) I would never offer anything in this forum that I could not back up with documented evidence. I thought I had made this clear in another forum. I did not take your comments personel, but more in the line of unfair feelings about me. I respect ever single comment in these forums, but personally do not feel that sharing our accomplishments as being un-kosher or any reason for a warning flag to be present. This, too, is just my opinion. Throughout all of my schooling, I won't go into how many years or where, but I was never offended by my collegues stating their position, education or experience. I encouraged it. In my current position (again, I won't state that either), I deal with every category of welding related issues and welding personnel throughout the USA and have never been advised that feelings you feel are out of the ordinary. Again, thanks for your comments and I appreciate the response to my statements.

Chuck

By cmansonite (*)

Date 04-25-2005 22:10

Thank you all for the information. It certainly has been a spirited conversation! That is a lot of info to try to soak up, but I am glad to get it. Think I'll go enroll in a metallurgy class so I can understand everything groberts and cmeadows were discussing. Being a non-certified welder who cut his teeth 20 years ago on SMAW 1/8" 6010 @ 60 amps (the ex-navy instructor MADE me learn that way) who then progressed to GTAW repairing in the mold-making industry, most of that stuff is a little over my head, hence the question about filler metal for this application. Getting my hands on some Cronatron rod way-back-when sure made welding a lot easier, Harley. It's good stuff. I hope this is not too much personal info for Mr. Sims. Thank you all for the input! It has been very helpful. I value all of your comments.

cmansonite

By MBSims

Date 04-26-2005 01:19

No cmansonite, that's not too much personal info for me at all. I was a welder long before taking any metallurgy classes, and my Navy instructor made me weld 6011 pretty much the same way. I hesitated greatly to make the comments I did, but I stand behind them. I do enjoy hearing about peoples experiences and backgrounds because much can be learned that way. I offered a word of caution based on my past experience.

By - Date 04-27-2005 15:36

Mr. Sims,
I will make this my last e-mail regarding these issues. Please let me say that I'm glad you're not opposed to learn of other people's experience and background, which appears to contradict your feelings in your prior comments. Please don't take this personal, but I would have never made the comments you did when you've never had the opportunity to meet the person you directed them to. Like you, I certainly stand behind my comments towards sharing information based on each other's background. We should not make them if we're not willing to stand behind them. Saying that sharing these things is not kosher and should throw up a warning flag is not encouraging and is actually not being considerate to me, in this case.

Chuck