Pyrowear Alloy 53- Grain refinement

[Shaw123]

Pyrowear Alloy 53 material.
After forging grain coarsening occurred from the original billet.
A grain refinement heat treatment was attempted which achieved an improvement of 2 ASTMs. This was still not enough. The heat treatment was 920deg C for 4.5 hours with an air cool.
Should the time in the furnace effect the improved grain size?
Can anyone suggest a better recovery heat treatment?
Any help in appreciated

Shaw123

 

[TVP]

What is the original grain size? What is the desired grain size? What forging temperature was used? 920 C is too high a temperature for reducing the grain size. This temperature is used for carburizing, and can result in grain growth if the time is excessive.

 

[Shaw123]

Thanks TVP,

Billet grain size = ASTM 5-7
Forging grain size = ASTM 1-3
Desired grain size = ASTM 5
Forging temperature = 1120degC
A heat treatment of 920 for 4.5hrs AC reduced grain size from ASTM 3.5 to 5.5.

Shaw123

 

[EdStainless]

Is that forge temp correct? That looks high. What was the final forge temp?

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Corrosion never sleeps, but it can be managed.

http://www.trenttube.com/Trent/tech_form.htm

 

[CoryPad]

Carpenter lists 1120 [°]C, so it is correct.

Regards,

Cory

Please see FAQ731-376 for tips on how to make the best use of Eng-Tips Fora.

 

[EdStainless]

Sounds like it was at max temp too long, or there was not enough reduction. The forging should finish in the lower portion of the temp range.
Maybe they got carried away with the last reheat during forge?

= = = = = = = = = = = = = = = = = = = =
Corrosion never sleeps, but it can be managed.

http://www.trenttube.com/Trent/tech_form.htm

 

[Shaw123]

All parts were forged in one heat.
Has anyone got any idea for a recovery treatment?

Shaw123