Looking for some advice. What is the best way to reduce distortion with 420 material? Running parts hanging vertically from a fixture at 1950 with a 2bar quench 50% fan speed. I have the ability to hang the parts horizontally. Will this help with any distortion since the weight will be dispersed over a larger surface VS all the weight on a vertical end it is hanged from?

 

thank you

What designation system is that 420 in?  I assume the 1950 is degF and not C or Kelvin.  What type of distortion are you seeing?   Are the parts compact or outspread?

people tend to forget that the world is a big place when posting questions they leave out too many details.

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Parts running in a vacuum furnace at 1950F. Parts are not compacted. Hanging close but no compression on any parts.. The parts are coming in exactly to spec as we put them through a gage prior to running. We are getting various % of fallout on each trial run. We drop them in a gage to show any distortion. Looks to be getting expansion distortion.

And what system is the 420 in ?  Is that 420 stainless steel or Aluminum?   (At 1950 it's probably SS!)

Now as to compact vs outspread I was wanting to know if the parts looked more like a sphere or a starfish.  Changes in Cross section are a common issue in heat treating.

Also steel being hardened often changes size.  Was this allowed for in the spec?  (Generally why final finishing is done after HT!) Some alloys are more stable than others though.

we still dont even know what country this spec is from

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How many pieces do you have and what are the dimensions/thicknesses?