Welding Mild Steel to High Carbon Steel

  1. atlantis1980 New Member

    United Kingdom
    I have a job on the farm to weld brackets of mild steel (10mm thick) to a high carbon steel (tool steel) (20mm thick).

    I have experience of basic welding, but would appreciate some advice as I know this can't be done with standard rods.

    I have googled the subject and although a little wiser am still a little confused.

    From what I've gathered, I think I will use 312-16 rods, I have seen reference to pre-heating, but also other advice saying with a 312 rod this is unnecessary?

    Is there any particular technique for welding with 312 rods?

  2. whats the actual grade of material (BS/EN No.) and how structual is the part......
  3. atlantis1980 New Member

    United Kingdom
    I don't know the exact grade only that its very tough and have been told its high carbon steel.

    Its not really structural in the sense if it fell off, the machine is still perfectly useable.

    When the part was sent by the manufacturer, he just said its high carbon steel and when they mig weld they use Nickel Chrome wire.
  4. nickk Member

    am not familiar with that electrode ,but i would pre-heat to dull red to avoid cracks on cooling & use a nickel/chrome electrode.
  5. So is the material a nikel alloy? or just high carbon.
  6. atlantis1980 New Member

    United Kingdom
    A high Carbon steel as far as I know.
  7. 312 consumable then. Without knowing he grade of material its a bit guess work, however id be inclined to treat as EN24T theres some advice here.....

    TechnicAL may be along to put me wright tho.
  8. TechnicAl

    TechnicAl Member

    Without knowing the grade thats what I would advise.
  9. atlantis1980 New Member

    United Kingdom
    Thanks for the advice...

    If this isn't to stupid a question, can I just pre-heat with my gas torch and would I have to heat the whole lot or just the localised area where I will be welding?
  10. yes torch is usual and test with temple sticks at location, Its important to leave the area for a minute then test, to allow surface temps to settle. getting the whole material to an even temp is desirable, however this isn't always possible depending on the size shape etc..