In this work, the effect of heating rate on the phase transformation temperatures was investigated using dilatometry analysis. Continuous heating and isothermal holding above Ac3 temperature on microstructural evolutions in additively manufactured (AM) parts of Fe-Cr-Ni maraging stainless steel were studied. The microstructural features developed within the heating processes were characterized employing electron backscatter diffraction and transmission electron microscopy. Austenite reversion was found to take place in two steps for the AM parts by a diffusive mechanism as well as the precipitation reactions. Although grain refinement occurred during the austenite reversion of the continuously heated samples, the microstructure showed a coarser grain size after isothermal heating. The crystallographic orientations developed after the heating processes were different from those of the initial ones implying the absence of the austenite memory effect.
|Journal||Metallurgical and Materials Transactions A: Physical Metallurgy and Materials Science|
|Publication status||Published - 2022|