Soft annealing 1

[bubble13]

Hello,
I have some high carbon(1%C) bearing steel,i followed the soft annealing procedure to prepare it for machining.what I expected to get was spherodised cementite in a continous ferrite matrics, unfortunately,when i see the microstructure i get somekind of ferrite so i assumed there is something wrong during the soft annealing i.e it seems to me it didnot even reach to the A1 temperature during the the soft annealing ,so the folowing heating and cooling cycles doesnot have any effect if we at first place are below A1 temperature.
so my question is
Can I again try to austentise it again and follow the soft annealing procedure? will there be any consequences?can i still get the microstructure that i need?

 

[arunmrao]

You can reheat treat the material,without any problem,provided only that you have enough stock to machine .

I have not failed. I've just found 10,000 ways that won't work." — Thomas Edison
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[Robertmet]

"somekind of ferrite" Do you mean 'pearlite' ? Are you getting any grain boundary carbides ? Yes you can reheat treat.You could anneal or subcritical anneal .

 

[bubble13]

Thank you very much
yes I mean 'pearlite' but no grain boundary carbides.first of all what I should be doing was intercritical annealing(it should have been partially austenitized before holding and slow cooling) but mistakenly what has been done was subcritical annealing around 680C which gives me the wrong microstructure. so now i understand that i still have the chance to reheat it above A1 and hold and slow cool to get the spherodised carbide evenly distributed in the ferrite matrics. but will there be any distortions? any decarburisation?

 

[CoryPad]

There should not be distortion if you cool slowly.

Yes, you can get decarburization.

 

[dbooker630]

A subcritical or spheroidize anneal still should give you the desired results. You may have to extend the time at the spheroidizing temperature or raise the temp to 690-695C.

 

[TVP]

Bearing steels like SAE 52100 (100Cr6) are almost always annealed in the intercritical region in order to break up the blocky pearlite. Extended subcritical annealing tends to produce incomplete spheroidization in these regions. Either way, there should not be a problem with distortion or decarburization as long as the process is properly controlled.