Any heat treat experts here ?

[Camacho]

I am oil quenching a starter gear welded to a shaft . And was wondering about tempering temp and time .
Just want a hard surface and dont want it too brittle .
This isn't a rocket ship . And will be done in a garage so lets keep it simple lol

Thanks

 

[Grease Monkey]

I bet @parker@gearone would have the answer to this.

 

[Sausage450r]

Heat it a dull red and just submerge in old used motor oil until cool. It really depends on what base materials are and what filler was used.

Something like that preheating before welding and then using a ni-55 nickel welding rod would probably be best. I dont post treat typically unless its a tool or die that will be having parts pushed in/out.
Order of operations:
-clean
-Pre-heat
-weld
-immediately wrap in heat blanket and allow to cool at its own rate in the blanket

I would aim to relieve the stress at the weld site this way vs. tempering metal by heat treating

 

[parker@gearone]

Heat it up bright red, hold the bright red for about 30 seconds for every 1 inch of cross section on the material. This "heat soak" allow it to harden a little past the surface.

then quench part, make sure you hold the quench for a few minutes. we want to make sure we fully cool the part through.


Throw it in the oven 375 F for 90minutes, let it cool to ambient temp. then another 375 f for 60 minutes.

Note, clean the part well before temper don't want to smoke out the house...

 

[Camacho]

Heat it up bright red, hold the bright red for about 30 seconds for every 1 inch of cross section on the material. This "heat soak" allow it to harden a little past the surface.

then quench part, make sure you hold the quench for a few minutes. we want to make sure we fully cool the part through.


Throw it in the oven 375 F for 90minutes, let it cool to ambient temp. then another 375 f for 60 minutes.

Note, clean the part well before temper don't want to smoke out the house...

Perfect thankyou

Does the time or temp between quench and tempering matter ?

 

[Rockwood]

Perfect thankyou

Does the time or temp between quench and tempering matter ?

Fully cool is all that matters.