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  1. seep555

    No REX in HEA at high temperature?

    Thanks a lot! And how would you explain that at low temperature (<0.5Tm) this mechanism seems to be different and there are small REX grains (or at least free of dislocations)? And what about still very high density of dislocations after long heat treatment at T>0.5Tm? Isn't recovery about...
  2. seep555

    No REX in HEA at high temperature?

    I see... I also found this high density of disocations in Al alloy AA1235 after annealing... It was explained by nanoprecipitations blocking dislocations movement. My idea for now are nanofluctuations of chemical composition, and in case of HEAs this effect may be strengthened by lattice...
  3. seep555

    No REX in HEA at high temperature?

    I am working now on a high-entropy alloy which seems not to recrystallize at high temperature annealing (>0.5Tm). It is hot forged and has grains of few tens of um with many nanocells inside them. At high T it seems that grains are growing but not recrystallizing and dislocations remain stable...
  4. seep555

    Ultra-fined/nano structure after HOT FORGING

    Thank you! Anyway, it's quite interesting from the theoretical point of view, don't you think? As far as I know obtaining UFG structure is possible only by high deformation techniques, and forging (hot, so also recovery and recrystallization occur) is rather not one of them...
  5. seep555

    Ultra-fined/nano structure after HOT FORGING

    Hello everyone! Is it possible to obtain an ultra-fined/nano structure (single grains of 200nm in the structure) just after hot forging? I have to steels with slightly different compositions. Both of them are rich in Ni and Co, there is also a big amount of Cr and Mn. In one (after the same...
  6. seep555

    Nanostructured HEA without strong deformation

    Hello everyone, I obtained a nanostructured (or maybe rather ultra-fine grained) material (grains of about 200nm) just by hot forging as-cast alloy. This material is based on high entropy alloy (Fe, Cr, Ni, Mn, Co) and it possess FCC structure. Is it possible that some kind of transformation...
  7. seep555

    Rolled samples treating for microtensile test

    But when you measure the hardness you also have to polish the samples first, right? And what exactly do you mean by picking?
  8. seep555

    Rolled samples treating for microtensile test

    It's not enough just to polish the sample a little after heat treatment?
  9. seep555

    Rolled samples treating for microtensile test

    Hello everyone, I have to do a heat treatment (600C and 1000C for 24 hours) of rolled samples (1mm thickness, 40mm length) of austenitic stainless steel and I am not sure if it's ok if I just use argon atmosphere (24h is not very long in my opinion) or it's better if use a glass protection...
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