Fractured 4130 CrMo Tubing

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Recently completed some destructive testing after welding t-sections of 1-1/2" x .058 wall 4130 "N".  Samples welded with a Lincoln Precision TIG 375 using 1/16" Thor tungsten and .045 ER80S-D2 filler.  All tensile fractures were manually induced via an Enerpac cylinder and heavy-duty rig.  The samples recorded tensions of 8k lbf, 17k lbf, and 18k lbf.  The 8k lbf sample (dullest gray) was preheated with an O/A rosebud to bright orange and immediately quenched into a bucket of water prior to the test......increase brittleness.  Note, the longer end of the "t" had a threaded fastener to connect to the destructor rig.Notice the plastic deformation of the t-section's cross-section (short tube) induced prior to ultimate failure.  Common values for 4130 ultimate strength are 92-93 ksi.  Strong!  Attached ImagesLast edited by ManoKai; 12-14-2014 at 02:49 PM."Discovery is to see what everybody else has seen, and to think what nobody else has thought" - Albert Szent-Gyorgyi
Reply:Continued.... Attached Images"Discovery is to see what everybody else has seen, and to think what nobody else has thought" - Albert Szent-Gyorgyi
Reply:I dont know much about welding tubes and whatnot. But it seems the welds failedevery time I have done of of these tests where they attempt to break the part the welds never fail its usually the tubing itself that failed. has alot to do with penetration and heat input
Reply:4130 has a yield strength of 63ksi and an ultimate tensile strength of 92-93ksi in "N" condition.  The filler used for these tests has a UTS of 80ksi.  All welds were made with a mindset to minimize the total heat input.  We did more samples and in a few cases the tube fractured symmetrically outside the weld line, as you referenced.  Statistics.Last edited by ManoKai; 12-14-2014 at 06:29 PM.Reason: numerical correction to 4130 UTS"Discovery is to see what everybody else has seen, and to think what nobody else has thought" - Albert Szent-Gyorgyi
Reply:What happens when you weld it with 70S?...zap!I am not completely insane..Some parts are missing Professional Driver on a closed course....Do not attempt.Just because I'm a  dumbass don't mean that you can be too.So DON'T try any of this **** l do at home.
Reply:Any time to oxy-acet a test?
Reply:Great tech paper related to this thread...covers many different aspects, including pre-, post-, and both pre- & post-weld heat treating.Effects of Fillerwire Composition along with Different Pre- and Post-Heat Treatment on Mechanical Properties of AISI 4130 Welded         by the GTAW ProcessLast edited by Oscar; 12-14-2014 at 07:16 PM. 1st on WeldingWeb to have a scrolling sig! HTP Invertig 400HTP Invertig 221HTP ProPulse 300HTP ProPulse 200 x2HTP ProPulse 220MTSHTP Inverarc 200TLP HTP Microcut 875SC
Reply:Originally Posted by ManoKai4130 has a yield strength of 63ksi and an ultimate tensile strength of 92-93ksi in "N" condition.  The filler used for these tests has a UTS of 80ksi.  All welds were made with a mindset to minimize the total heat input.  We did more samples and in a few cases the tube fractured symmetrically outside the weld line, as you referenced.  Statistics.
Reply:quick look tells me where the weld starts and stops in laymens terms
Reply:@ zapster - we had 70-S2/6, but didn't try any.  These samples were my first attempts at TIG'n .058 wall 4130.  All prep work to the tubes was dialed in, but def applied excessive heat.  The bead profiles and net color sucked.  Starting to develop a rhythm for welding round members.....@ OldSparks - negative on welding with O/A.  That would be cool.  Next time bro.  Next time."Discovery is to see what everybody else has seen, and to think what nobody else has thought" - Albert Szent-Gyorgyi
Reply:Sil bronze ?...it would be less heat inputBacked my CATMA over your CARMA oops clusmy me  What would SATAN do ?? Miller Trailblazer 302 AirPakMiller Digital Elite  Optrel Welding HatArcair K4000Suitcase 12RC / 12 VSHypertherm PM-45Rage 3 sawRusty old Truck
Reply:Not trying to bash.  Im trying to make you better Mono.Those welds look like fidos butt and way too hot.Personally i like to "pulse" 4130 with my foot.4130 should come out looking like you've just welded stainless.Im sure the mig like tig master can chime in more.Miller Dynasty 200DXMiller Spectrum 250DMiller Millermatic 200Bunch of old blue dinosaurs....
Reply:Here's a good example of the color(s) you're looking for.http://weldingweb.com/vbb/showthread.php...ate&highlight=Miller Dynasty 200DXMiller Spectrum 250DMiller Millermatic 200Bunch of old blue dinosaurs....
Reply:@ Jon - you're absolutely correct.  Disastrous heat input and bead profile.  I did work the pedal and cooked the results.  Back to training time.  Thanks for the insight "Discovery is to see what everybody else has seen, and to think what nobody else has thought" - Albert Szent-Gyorgyi
Reply:ManoKai, did you fabricate the Enerpac destructos rig, or purchased? 1st on WeldingWeb to have a scrolling sig! HTP Invertig 400HTP Invertig 221HTP ProPulse 300HTP ProPulse 200 x2HTP ProPulse 220MTSHTP Inverarc 200TLP HTP Microcut 875SC
Reply:dont pulse it. just run it in one straight pass. it wont fail if it penetrates
Reply:Originally Posted by ManoKai@ Jon - you're absolutely correct.  Disastrous heat input and bead profile.  I did work the pedal and cooked the results.  Back to training time.  Thanks for the insight
Reply:@ Oscar - negative.  The tension rig was a HD setup with an Enerpac manual cylinder purpose built by an industry leader (Lincoln Electric) in OH.@ killdozerd11 - CuSi would be a cool test.  UTS is ~ 50ksi for silicon bronze.@ jonthetubroguy - ran a few 4130 tubes using a lensed #10 cup with 25 CFH and 1/16" REDs.  Hypodermic needle sharp.  Today.......trying some 1-3/8" x .120 wall 4130 on coped "T Joints".  Baselining 3/32" REDs, #8 cup, 16 CFH shielding, and 1/16" ER70S-2/6 fillers.  Setting the 200DX at 120A with pedal control.  Thx!   Will post the results."Discovery is to see what everybody else has seen, and to think what nobody else has thought" - Albert Szent-Gyorgyi
Reply:Well....just sold all existing stock of 1-3/8" x .120" wall 4130 tubing to a local CL buyer.  No more available for training/builds.  Working an angle to rip some next week To be continued ~ ~ ~ ~"Discovery is to see what everybody else has seen, and to think what nobody else has thought" - Albert Szent-Gyorgyi
Reply:Recent practice run of 4130 (.085" wall) for a "5F" D17.1 test. Attached Images"Discovery is to see what everybody else has seen, and to think what nobody else has thought" - Albert Szent-Gyorgyi