I've had lots of experience with both... 5160 does not play well with others...or with itself! That's likely the reason you got delamination...because that what 5160 does when you try to forge weld it. It can be forge welded flaw free, but that is the exception rather than the rule.

  That is.... assuming what you have is actually 5160. Ever since "Spec-Manufacturing" became the norm, those old charts circulating around the internet of what items are made of what steel are useless.

  Unless those springs were pulled from a pre 1980 truck, it very likely that the material IS NOT 5160.  Between then and now, there have been no less than 18 different alloys used for both leaf and coil springs, so saying it's 5160 is just a shot in the dark. 

  Hard experience has taught me to steer clear of 5160 when it comes to forge welding...using it dramatically reduces your chances for success right from the start.   Wrought iron also introduces an wide set of variables into forge welding....with near to zero carbon, working and welding temps are extremely high as compared to even low carbon steels.  In other words, you're not only handicapping yourself trying to forge weld 5160, but even more so when you throw in the wrought iron. 

   In the end,you can waste a lot of time, effort, and supplies trying to make it work....but its a lot like trying to ice skate uphill. 

Thank you Ed, 🙂  yes yes and yes. I understand leaf springs are proprietary these days/ high alloy steel and the wrought has almost zero carbon.....inturn makeing it extremely difficult,   that's the hole point of the project. I know it's been done before but I don't see it available for knife makers to work with. I'm a blacksmith and Damascus supplier striving to provide products that are unique and difficult, so goes this project and me with ice skates on and a winch line attached to my britches.......I have a large supply of both materials.  Last night I made a nother pice,  I placed printer card stock between the layers, mig welded seams all the way around leaving a small gap on corner after I welded handle on and let it cool down I let it soak in kerosene for few min then tossed it in the forge, got the pice up to 2900 degrees let it soak for 10 min at temp, drew it out with my press then back in forge and shut it down to let it cool down over night. Wount be able to grind the edges until Saturday.  The paper and kerosene.....are me doing a sincetific wild ass guess, hoping the wrought iron will absorb the carbon helping it bond.  Sorry about my spelling is very poor. Side not talked to a auction guy yesterday named Romey bromwich........we got side tracked from the sale and turned out he was a ABS journeyman and mentioned you by name,  it's a small world,   thank you agin Ed 🤠

 Romey!  I've not talked to him in a while.  He's good people!   

  If you're producing materials (damascus) for sale, I'd give any combo with 5160 in the mix a hard pass.  Sooner or later (I'd say sooner) it will cause you a lot of grief when a client comes across flaws in the material.  (Been there...done that.... and didn't even want the T-shirt!) 

  Another word of advice.... get yourself a supply of vermiculite, and a suitable container for annealing. While putting material in the forge and allowing it to cool down with the forge (as in overnight), can be used in a pinch.... it's just a "spotty" anneal.  

  If you're welding at those high temps (I understand you're doing it because of the wrought), make darn sure you thermal cycle to get the grain refined....otherwise that grain will look like a gravel road, and all the bad stuff that comes along with it.

  Best of Luck on the project!  Keep us posted on the progress!   

Thank you agin Ed,  great advice.   Having a master bladesmith like you around that cares enough to help us little guys out is such a amazing resource, thank you agin Ed and thank you to the American bladesmith society 😊 

Posted by: @chris-magnus

Thank you agin Ed,  great advice.   Having a master bladesmith like you around that cares enough to help us little guys out is such a amazing resource, thank you agin Ed and thank you to the American bladesmith society 😊 

As it should be Chris!  Best of luck with the project!