Not logged inAmerican Welding Society Forum
Forum AWS Website Help Search Login
Up Topic American Welding Society Services / Certifications / I have a situation and could use a lil input from the pros.
- - By Kix (****) Date 08-29-2007 12:29
Some of you might remeber that i was in the works of qualifying some welding procedures to D1.1 for welding armor plate or Hardox 500 anti wear impact resistent plate.  My question is how am i suppose to do this when the tensile pulls are not going to come out.  Everything else came out except for the tensiles.  Hardox 500 has a tensile of around 220MPA and the filler we are suppose to use is in the 90's.  Anyway as suspected the tensile pulls broke in the weld so is there anywhere in the code that covers what to do in my situation?  Thanks!!!
Parent - - By js55 (*****) Date 08-29-2007 15:34
Kix,
I'm not exactly sure what you are looking for, but if I may, I would be suspect of thinking in terms of looking to the code for solutions. Thats not what its for.
Only an engineering analysis can determine if what you are doing is adequate for the service intended.
If the code is imposed upon you by contract then it must be complied with, but I wouldn't look to it to solve problems.
Parent - - By swnorris (****) Date 08-29-2007 16:17 Edited 08-29-2007 16:20
Have you tried this link:

http://www.hardox.com/upload/Documents/en_recommend_hxwx_welding_11_v1.pdf
Parent - - By js55 (*****) Date 08-29-2007 16:46
Thanks Scott. I'll put that one in the library myself. Ya never know.
Parent - - By Kix (****) Date 08-29-2007 19:44 Edited 08-29-2007 19:53
I wasn't wanting to look to it to solve my problems, but more to see if you guys knew of any notes that had any material on my particular matter that would specify if i need to now go to engineering and tell them i can't qualify this to code or something that said if i get engineers approval can i still use this WPQR.  I'm thinking i have to tell the engineers that what we are doing will not qualify to code we need to get customer and engineering approval.  Is there any other code that would except this being what it is?  What does the mil code say about this.  We are useing the filler that is supposed to be used on the hardox 500,but even they told me the tensiles would never come out.
Parent - - By js55 (*****) Date 08-29-2007 20:16
Kix,
OK. Little slow on the uptake sometimes. How bout D1.1, 1.2. I am assuming your armor plate has yields in excess of 100 ksi?
I am also assuming you did not mean tensiles of 220 Mpa, which is approximately 35 ksi.
Especially since your 90+ksi filler busted tensiles inthe WM.
Parent - - By Kix (****) Date 08-29-2007 20:30 Edited 08-29-2007 20:33
Ok i'm sorry I made an oops we're useing ESAB dual shield E81T1-1-ni1mh4 witch has a tensile strength of 85,000 Psi and Hardox 500  has a tensile strength of 1500 N/mm squared witch comes out to over 220,000 psi if i did my conversions correctly.  Someone correct me if i'm wrong cause man sometimes i don't get enough sleep at night and the next day is brutal.;-)  Here is the e-mail i got from tech support at Hardox.

    The HARDOX 500 has a tensile strengh in the region of 1550 MPa or approximately 220 kpi.
There is no weld method today that can match that strength and the HARDOX wear resistant plates are not ment to be welded with matching strength. To avoid problems with mainly hydrogen cracking it should be welded with a soft filler material of 500 MPa or 70 ksi.

Bottom line is that you will never get a satisfactory result in a tensile test to full strength in a welded HARDOX 500. Either the weld or the HAZ will break first.

Best Regards,

/Hans Konradsson
Parent - By js55 (*****) Date 08-29-2007 21:01
I just think that no matter how you skew this thing that Hardox is not appropriately qualfied per D1.1. You can test it by using D1.1 method, but IMO it isn't valid to that code.
You could of course apply a philosophy similar to 4.15.2 (obviously this is for processes not materials) with EOR approval. But why would you want to?
Its a square peg in round hole. Better to just lathe your peg.
Parent - By CWI555 (*****) Date 08-30-2007 03:03
Kix,

I would have to agree with js55. I don't think D1.1 is going to cover that. While I've been out of the mil spec loop for some time now, I would think they'd have something to cover this. The use of D1.1 as a guide yes, but not as a code. Your email states it correctly, there is no welding process in the public domain that will match that grade of alloy that I am aware of.

Regards,
Gerald
Parent - - By ssbn727 (*****) Date 08-30-2007 05:57 Edited 08-30-2007 08:47
Hi Kix!

I was reading the brochure that Scott posted in this thread, and what I read on page 4 states:
"The following alternatives are available when selecting the yield strength of the filler material:
1) Undermatching weld metal (the weld metal has a lower yield strength than the parent metal).
2) Matching weld metal (the weld metal and the parent metal have the same yield strength).
3)Overmatching weld metal (the weld metal has a higher yield strength than the parent metal).

So, after reading that, have you tried welding with say a E10XT-X, E11XT-X, or a E12XT-X wire yet to see if you may get closer to what you're looking for in your tensiles? Of course, I would first try to contact SSAB Oxelosund and find out if this would make a difference or not. ;) I would also incorporate a tempering bead technique similar to what is performed when welding HY-80, HY-100 steels and their equivalents... Are you absolutely sure that the required tensile strength must be at least the same as the parent metal???

Finally, I would double check that the filler metal has a hydrogen content less than 5ml/100g of weld metal before concluding that it's safe not to preheat the joint prior to welding. I would also use PWHT in order to get close to what you're looking for in tensile strength if possible. Edit! Forget the PWHT because I just found the data sheet for Hardox 500 which recommends no further heat treatment yet, I do'nt know for sure if they are including PWHT in their statement... Interesting in the fact that it does'nt list the yield or tensile strengths of this grade as opposed to the other data sheets that do... I wonder why???

http://apps.ssabox.com/pdf/datasheets/us_datasheet_hx_500_v1.pdf

Anywho, we got a US Corporate office right here in Coraopolis (Less than 5 miles from my residence) and I guess a Hardox distribution center in Pittsburgh, on Neville Island:
http://ssabhardox.openfos.com/
I'm going to call them tomorrow and find out what's the correct tensile strength for the Hardox 500, and here's an e-mail addy for the Area Technical Manager - Kjell Backman: kjell.backman@ssabox.com
Maybe this person can shed some light for you on your situation.

The thing that bothers me most about this problem is why this Hans Konradsson writes you stating:
"There is no weld method today that can match that strength and the Hardox wear resistant plates are not meant (he spelled it incorrectly :) ) to be welded with matching strength" yet, it clearly states in the .pdf that alternatives are available besides using undermatching filler metal... Then he continues by writing: "To avoid problems with mainly hydrogen cracking it should be welded with soft filler material of 500 MPa or 70 ksi." In the .pdf that Scott posted it clearly shows in the chart on the first page on the left hand side that Hardox 500 calls for at least an E80XT-x wire and can go as high as an E90XT-X so, where does his logic fit in with using a "soft filler material of 500 MPa or 70 ksi"???

If this is true then who in the Sam Hill came up with these specs in the first place??? Somebody should've known beforehand that these tensiles could'nt be achieved realistically!!!
If you ask me??? Someone is trying to bury this FUBAR, and hand it over to your lap!!! I have one suggestion for you: CYA - PERIOD!!!

Now, I've heard in the past that with the suggestions I gave above, that one can achieve significant improvements in their tensile limits by incorporating all of the above mentioned practices, although I personally have'nt tried it on Hardox 500. I wish you all the best on this one Kix!!!

Try this link from SSAB Oxelosund, it has many"Technical recommendations" .pdf's on welding weldox & hardox:
http://www.ssabox.com/templates/brochures/InformationMaterial____10048.aspx

Respectfully,
Henry
Parent - - By Kix (****) Date 08-30-2007 12:23
Yeah, but isn't there rumor going around that the military is going to possibly be adopting D1.1 for their recognized code.  I've got a buddy that works for Northrop Grumman Ship Systems and they use some mil spec and he is going to see if our procedure will qualify under one of the mil spec codes for the heck of it.
Parent - By Kix (****) Date 08-30-2007 15:42
Ok i got some info from engineering about the performance specifications for this military contract.  It says all welding shall meet the design and fabrication requirements for cyclically or staticlly loaded weldments, as supplied by the AWS D1.1 for steel, D1.2 for aluminum and D1.3 for sheet steel and B2.1 for stainless steel.  So i'm like mmmm we got issues.lol
Up Topic American Welding Society Services / Certifications / I have a situation and could use a lil input from the pros.

Powered by mwForum 2.29.2 © 1999-2013 Markus Wichitill