Thread: Metallurgy Question

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As far as the weld question goes, some people will have different oppinions on that. As for me, I wont comment on it because I am still stuck between each oppinion. In a way though, the heat can mess up the metal there and cause a weak spot around the weld but if done correctly and you used TIG or MIG and kept the heat down then it may be fine. Like he said above, the weld should be stronger than the metal around it if done correctly and you should be able to bend that welded section and not break it.

I do know this, if done incorrectly, they WILL break. My brother had a 39 Ford that had the spindle steering arms "dropped" before he got them. He had driven all over in that car, at the drags (13.80 at 100 mph) drove it all over the state. One day he went down the freeway (probably 80 mph or so knowing him) twenty miles or so and back again. As he pulled up into the driveway at the shop he decided to back up and go to the back of the shop. He dropped it in reverse and the steering wheel spun in his hands! That was it, snapped right off! Knowing that he had just been tooling down the road in this car and he did NOTHING for it to break, just turned the wheel, he was pretty shaken up to say the least.

Heat slowly and COMPLETLY then bend slowly and let it cool down slowly.

Brian

Maybe this would be one of the things that cryogenic freezing would help with . They freeze the part to ridiculous temps and it compacts the molecules and hardens the steel. Pretty new technology.

"cryogenic freezing"

No, no. This is an application where you heat and bend the arm to exactly the shape that you desire and then sent the arm off for proper heat treatment. You guys that destroy the properties of metal and then slap the part back on a front end are playing with fire. There is not a significant gain of tensile strength or ductility from cryogenic freezing. (After normal heat treatment procedures, of course)

It will work ,I am just saying that area will not be 100 percent .Its one of those things could be today ,6 months from now who knows.

Thats why i put the maybe in there I am no expert and will never claim to be

Heh, the MAYBE is the clue, come on now, pay attention! You gotta capitalize that next time. LOL

better listen to Lucforce , he is right , yeah i know the weld is stronger but what about the rest of the part after being heated and cooled rapidly ????

look at this link Cryogenic Tempering - How Cryogenics Improves Metal Durability from One Cryo

I think I just won't start messing with that Camero arm. I plan to try connecting the drag link to the spot on the tie rod shown in my posted picture. Then the cross over drag link will be bent up, parallel the tie rod under the oil pan, then angle up again, if needed, to connect with the pitman arm. I have had some difficulty finding a dropped pitman arm to fit a tri-five box. I may move the box forward and down a bit. Then I could cut the shaft and use borgeson type joints. Or, maybe I should just use a Vega box.

1) It is unlikely that a welded part will have the strength as the original forged part, heated and bent or not. Area rules the day here IMO.

2) Most forged steels will retain most of their of strength when heated and formed. Thick suspension sections are typically forged very hot (cherry red) and do not rely on cold working or tempering to enhance mechanical properties.

3) Don't weld on or heat and bend on any structural member unless you a) know what metal it is you are working worth or b) have years of successful experience working with very similar parts.

Kitz

The forging process IS a high temperature bending process, so the metalurgy IS correct for high temperature bending!

What's the benefit for this swap? It looks like you still have only one eye for the tie rod, so you'll still need that "double" tie rod end for the drag link. Are the steering arms the right length? Are the tie rod ends at the proper height to eliminate bump steer? Is the Ackerman angle correct?

If the line through the drag link ends is not horizontal, you will have bump steer. In addition, if you are using a double tie rod end and your drag link is not horizontal, your steering wheel won't return to the center position after each turn, because the pressure of the drag link on the tie rod will cause it to twist each time you turn a corner. Bending the drag link or the tie rod to clear obstacles will reduce the stiffness of the link.

"The forging process IS a high temperature bending process, so the metalurgy IS correct for high temperature bending!"

My concern is not the bending to get the desired shape. The problem comes with the temperature that the metal is taken to and then the physical method of the bending, followed by the cooling method used and heat treatment used.

If not done correctly, the metal will have stress fractures, too high ductility, or be too brittle. Frankly, with the time that has been spent on this thread, he could have heated and bent the arm, and hat it properly heat treated.

COULD be a forged or a simply cast piece.
probably doesn't have a HUGE load on it anyway,
relatively speaking.
watch the front end geometry.

could be mild steel, hardened (+quenched)to martensitic/austentite
microstructure, and normalized (reheated to a lower temp) for less
brittleness. can't determine this without polishing, etching,
and microstructure analysis or Brinell/Rockwell hardness testing

find a good welder- you'll be fine

if you heat up+ bend maybe stay away from wear points-
what the original heat treating was for anyway, not for load

I'll scan/post some heat treatment/metallurgy
pages when I return to work this week
(12 years- metallurgical lab here B.S.- real college woohoo)