Segregation engineering enables nanoscale martensite to austenite phase transformation at grain boundaries: A pathway to ductile martensite

Subgrain lath martensite mechanics: A numerical–experimental analysis

“…One example is the quenching and partitioning (Q&P) processing, where austenite layers thicker than those considered here are promoted. An even more recent example is the "reversed" austenite obtained in maraging steels (Raabe et al, 2013). After processing, the interlath austenite films reveal, at least partially, a KS orientation relationship with the adjacent BCC laths.…”

“…Austenite layers are used to improve toughness and ductility of martensite in the new generation of advanced high strength steels (AHSS), recently presented in the literature (De Moor et al, 2008;Raabe et al, 2013). One example is the quenching and partitioning (Q&P) processing, where austenite layers thicker than those considered here are promoted.…”

Atom probe tomography reveals options for microstructural design of steels and titanium alloys by segregation engineering

“…Besides these confined types of chemical and structural changes of lattice defects also conventional phase transformation and phase growth can occur at segregation decorated internal defects when the system is (in some cases locally) rendered into the two-phase regime. Here, we provide some examples how these different types of segregation phenomena and confined structural states at lattice defects can be used to design complex microstructures in metallic alloys by using simple heat treatments [12][13][14]. We give examples of corresponding segregation effects, complexions and phase transformation phenomena in Fe-Mn steels taken from earlier work [12][13][14][15][16][17][18][19].…”

“…The martensitic phase is visualized through the presence of multiple nano-sized intermetallic precipitates which formed upon heat treatment at 450°C for 48h. The results are taken from earlier publications [12,13,16]. The design of such martensitic maraging steels, containing also regions where martensite to austenite reversion occurred after preceding massive Mn segregation, was the basis for the development of the so-called maraging TRIP steels.…”

“…The sample was homogenized and heat treated at 450°C for 48h. The data were taken from a preceding paper [12,13,16]. In this case no complexion was formed but instead regular confined phase transformation (reversion) from the martensite into the austenite.…”