Qualifying a Procedure for AR-500 STEEL (Need Advice)

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Hi Everyone-I've been tasked with qualifying a WPS to ASME IX or AWS D1.1 with AR-500 Plate and E71T-6M FCAW.We did our preliminary 1/2" PQR plate with a 250 Deg F preheat and air cooled afterward.I put it on the bend test just and it didn't bend, Just flexed and then snapped in half with sharp edges and a pronounced grain structure.Does anyone have any recommendations for qualifying a WPS for AR-500?Any help would be appreciated.
Reply:Did the fracture happen in the base metal, the fusion line, or in the weld metal?Benson's Mobile Welding - Dayton, OH metro area - AWS Certified Welding Inspector
Reply:There is not a definite answer to this i don't think. AR500 steel is very hard and brittle. Used a lot as wear plates or target practice. Welding ar500 steel could result in lamellar tears, weakening of the steel structure itself. I have used 8018 on it.. We had some several years ago come in the shop It had to go to some gravel company and wanted it welded to mild steel to weld onto the hopper bottom. The gravel and sand was wearing out the steel so fast they needed a new solution. We welded it with 8018 to the mild steel plate. They then took the piece back to their yard and welded it into the bottom of the gravel hopper where it feeds into the conveyor. 8018 Low hydrogen rod should have enough elongation and tensile strength to possible let you bend. From what i heard it lasted several years before they changed it out again. Bending this material as a bend test on 1/2" plate i don't think it is going to bend to pass a test. That's my personal opinion. I am no professional with AR500 steel though. Only welded it one time. We did no bend tests(We only stitch welded it to the mild steel plate). It was just used as a wear plate. Putting too much heat to the AR500 and then cooling will weaken its structure from what it is originally intended for. Why are you trying to qualify this procedure? What is the application? what size wire will you be using? is the 1/2" plate Single V groove or Double V groove?Did it look like this? After it snapped?Last edited by AndrewDavenport89; 04-24-2015 at 09:31 AM.
Reply:I don't think a bend test is Appropriate for steel as hard (brittle) as ar500
Reply:It broke in the weld metal.Looked just like the pic above.This is for a pipe mill for a very large ISO company. Maybe I'll ask for a deviation from their requirement for a WPS on this one.
Reply:What is the pipe mill doing with this steel? I don't get what the application is for. If we knew exactly what it is going to, used for we might can get a better insight on advice to give. They might could just stitch weld it onto something that way they don't overheat the product. A very large ISO? ISO is (International Standards Organization) It is a governing body of codes and standards companies must practice. Now this pipe mill may be a member of the ISO. They should already know a procedure for this (*If there is one specifically for this*). Especially coming from a pipe mill they have Metallurgists that should know exactly what to do. Or possibly change your steel choice for a product with more weldability.Oh and AR500 steel is not suitable for structural applications.http://www.chapelsteel.com/ar500-ar500f.html
Reply:Originally Posted by Firemanmike69I don't think a bend test is Appropriate for steel as hard (brittle) as ar500
Reply:If by some chance your outfit comes up with a solution for weldability on AR500 to AR500 steel I am sure i speak for everybody we would like to know your procedure for a satisfactory weld, bend, UT or whatever means of inspecting that weld. Im with CEP on this try UT. Destructive testing might not work in this case. I also think that you will find incomplete fusion, lamellar tears or hydrogen cracking if you UT the weld. I am pretty sure you need to UT the Heat Affected Zone as well to check for tears. The heat input is what is going to get you on this weld.
Reply:Bending a coupon is nuts with AR.The reason you want a WPS is so the welder doesn't do something or use something that won't work well for the material and what you are doing with it.With AR, you can have the pre-heat wrong, have the energy input wrong for the section, use the wrong filler, use the wrong flux and have a technique so bad that a sound weld is impossible.The WPS covers everything but the technique, that is observed. Testing for what happened when an apparently sound weld failed gets pretty involved.Good luckMatt
Reply:Thanks guys.It's for a hot slag chute in new construction at the mill. This is why they had abrasion resistance material on the drawing.I only mentioned ISO because they are strict and have specific requirements to follow.I agreed that UT will make us feel confident that its a clean weld without cracks, but that doesn't satisfy the requirements of either AWS or ASME for procedure qualifications.I'll post if we come up with a solution. I doubt it's going to happen though.
Reply:Check with the steel mill and Lincoln with weld requirements and WPS for material .