Structure evolution of martensite under tempering is commonly considered in terms of the dislocation density decrease and the carbon re-distribution together with related carbide reactions, however I've never seen accurate investigations of how the packet-and-lath structure evolves. Meanwhile the tempering temperature, say 650 C, may be quite sufficient for migration of boundaries (anyway, high-angle ones) between differently oriented laths. The problem is practicable as creation (growth) of fresh HABs by tempering would refine the effective structure element...
Thanks a lot, I will check. If you, occasionly, run into something of the kind as well, I will greatly appreciate transmitting the REFs to me.
However, as I remember, the works you mean considered super-low carbon steels tempered at about 700 C. Meanwhile I implied the problem different in what follows.
1) Martensite is just low-carbon (say 0.1%C or even more) whereas temperature is closer to 600 C.
2) Some Laths do not bulge nor take smother shapes, but just grow keeping thin. Thus lath appearance remain morphologically almost the same, only orientation distribution among them changes...
Of course I have got some reasons to put such a strange question, and the underlying mechanism in this case should be apparently different from what you mentioned.
Alexander
Dear Alexander,
I see. They studied 0.1C,0.2C and with micro-alloyed steels, and the samples are tempered from 350-650 deg. However, they didnot compare the orientation or morphology change in the blocks or packets during tempering, though they showed KAM data. The KAM data is used for finding recrystallized grains.
Xinfu
Dear Xinfu,
what you said is one more reason to particularly investigate the evolution of OR variant spectrum in martensite under tempering and, ideally, to directly detect undergoing LOCAL events.
Dear Alexander,
I dont uderstood why this question is adressed for me, I not ivestigate the martensite in steel ?
Dear Yu. R. !
I did not address you personally but just put the question in RG media. Probably, RG automatically informed you as you follow my page or because of key word "boundary" related to you.
Best regards,
Alexander
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