where does bainite come from 1

[onestout]

Where does bainite come from and how do you prevent it? We have a couple furnaces that don't like cetain gears and are trying to figure out this problem. Thank You.

 

[diamondjim]

You might just want to search on bainite on the web
but here is one that might be helpful. You might
spec out the steel and heat treatment.

http://www.principalmetals.com/glossary/bdoc.htm

 

[Carburize]

If you are using exactly the same heat of material and the same part geometry then the cause is most likely cooling rate related.
If you are using different heats of material some could have lower hardenability than others which would affect the microstructure after heat treatment.

 

[metman]

What is the alloy and process? Is it carburized and is the Bainite in only the core or in case and core...?

 

[Salvatio]

Bainite may only form at a right time at a right temperature. As like martensite, banitic transformation is a rapid transformation, but not as fast as that of martensitic transformation. Depending on the composition of the steel, intra/inter-granular bainite may form.
Perhaps in your case, the quenching process is not rapid enough, or slow enough to hinder the transformation of bainite. Tendency of bainite transformation increases with decreasing carbon content in carbon-steel under quenching process, as the time required for bainitic transformation decreases with lower carbon content. Other alloying elements may also affect this.