No announcement yet.

heat treatment of SAE 4140 steel

  • Filter
  • Time
  • Show
Clear All
new posts

  • heat treatment of SAE 4140 steel

    I was wondering if anyone can verify or ? my findings. Have found in Lincoln's Procedure Handbook of Arc Welding (6.1-29) that SAE 4140's preheat, postheat, and interpass temps when welding with lo hydrogen electrodes is 600-700 deg F for 1/2-1" stock. Is this accurate? What are pre- and post- heat times for 4140 using a rosebud? Sorry for so many questions. Still a student and beginner. Still so much stuff to learn.

    Thanx for ANY replies.

    Amber H-B
    amber h-b

  • #2
    there's no set "time" for allowable pre/post heat. your best bet is to go to a welding store and buy a "temp stick" for that heat range. as your heating the steel, touch the stick to the metal. It will melt when correct temperature is reached.


    • #3
      I have welded a few 4140 aluminum casting mold dies in my shop. I only heat up a bit usually enough to get the chill out. I also weld these with mild steel filler by mig gun or tig welding.
      Jerry Streets
      J P Streets Welding LLC


      • #4
        4140 is a HTLA steel and preheat, interpass and postheat are important. My ASM Handbook shows the suggested preheat at 450 F to 550F, Lincoln is a trusted source and I would not hesitate to follow their suggestions, even if there is a slight descrepancy in temperatures. A temp stick or a thermometer of some sort is essential for accurately maintaining your temperatures. Try to heat the steel up to temperature one or two inches from the area to be welded.
        Last edited by Mike Sherman; 06-04-2003, 07:26 AM.
        Mike Sherman
        Shermans Welding