Heat treat to change color?

[Barncat]

I have a 1/8" thick disc of either 303 or 304 stainless(can't remember which) that I want to turn a golden color. How do I heat treat it to turn and stay that color? Do I heat to Golden and try not to overshoot, then quench in clean oil? Or do you go to a different color to make the finished result be gold in color? I will be using an oxy/acetylene torch for heat.

 

[benmychree]

I have not observed S/S to turn color from heat, except black when welding on it.

 

[RJSakowski]

I have a 1/8" thick disc of either 303 or 304 stainless(can't remember which) that I want to turn a golden color. How do I heat treat it to turn and stay that color? Do I heat to Golden and try not to overshoot, then quench in clean oil? Or do you go to a different color to make the finished result be gold in color? I will be using an oxy/acetylene torch for heat.

Stainless steel will run colors like steel but I believe it is at a higher temperature. From my experience, the colors are harder to control, particularly if you want a light straw to amber color. If a uniform color is desired, I wouldn't use a torch. An oven would be a better choice. When you reach your desired color, you should quench to stop the color run. Water would be sufficient. My experience with stainless is that the color is very durable. I believe that the color is due to chromium oxide rather than iron oxide on steel. I would experiment with some scrap material first to get the process down.

Here is some information on heat coloring stainless. https://www.bssa.org.uk/topics.php?article=140

 

[Barncat]

Well, I got a golden color, and it does seem durable. The torch doesn't heat very evenly, but I got it figured out enough so I can move on. HSS shown for reference color. Thanks!

 

[eugene13]

I like the pattern in the colors.

 

[darkzero]

Kind of reminds me of all the SS304 headers I used to install. By the second day they would turn a nice golden color which I loved. Too bad they didn't stay that color though.

 

[Barncat]

I like the pattern in the colors.

I will call that pattern a design improvement. It was from facing it. Wasn’t too noticeable until the color changed. It feels really smooth to the finger, but does really stand out appearance-wise. Not sure if I did something wrong facing it to get that pattern.

 

[mikey]

It's called chatter.

 

[Barncat]

Tool was on center. Maybe need to lock the carriage next time? Or slightly change the angle of the tool?

 

[mikey]

Might try decreasing speed and/or increasing feed.