Tensile properties and work hardening behaviors of ultrafine grained carbon steel and pure iron processed by warm high pressure torsion

Nanocrystalline steel obtained by mechanical alloying of iron and graphite subsequently compacted by high-pressure torsion

“…In other studies, carbon steel with different carbon contents was subjected to HPT, and the grain size was 200 nm after HPT of Fe-0.45 wt.% C at 7 GPa and 673 K [23], 120 nm after HPT of Fe-0.45 wt.% C at 6 GPa and 623 K [25], 10 nm after HPT of Fe-0.6-0.8 wt.% C at 7 GPa and 300 K [21], and 20 nm after HPT of Fe-1.2 wt.% C at 10 GPa and 300 K [20]. The larger grain sizes as compared to the $20 nm found in this study reported in [23,25,32] are most probably due to the elevated processing temperatures of 673, 623, and 813 K. In this study, samples containing 0.4 wt.% C were subjected to HPT at 523 K, resulting in a grain size of not more than 20 nm, while in [25] and [23], Fe-0.45 wt.% C subjected to HPT at 623 and 673 K at comparable pressures of 6 and 7 GPa, resulting in a grain size of 120 and 200 nm, respectively. Herz [33] performed isochronal annealing experiments on Fe-0.4 wt.% C powders after MA for 100 h at different temperatures.…”

“…[20][21][22][23][24][25][26]. Korznikov and co-workers [20] as well as Ivanisenko et al [21,22] analyzed the changes of high carbon steel (carbon content 1.2 wt.% and 0.6-0.8 wt.%, respectively) under HPT and found complete dissolution of cementite and the evolution of structural components with a mean size of 10-20 nm, whereas Zrnik et al [23], Bayramoglu et al [24] as well as Ning et al [25] found structural components with a mean size of 100-200 nm in AISI 1045 (0. 45 after HTP [26].…”

Microstructure evolution in a single crystal nickel-based superalloy joint by linear friction welding

“…Fracture of the tensile specimens occurred in the DD6 PM, as shown in the Fig. 2, which is attributed to the fine grain strengthening in the WZ and the work hardening in the TMAZ [28,29].…”

Formation and evolution of structure-phase states in rails after drawn resource

“…Namely, (1) the process of cementite particle cutting followed by their carrying out in the volume of ferrite grains or plates (in the structure of pearlite); (2) the process of cutting followed by the dissolution of the cementite particles, the transition of carbon atoms on dislocations (in Cottrell atmospheres), the transfer of the carbon atoms by the dislocations into the volume of ferrite grains (or plates) followed by the second formation of nanosize cementite particles. Other possible transformation mechanisms of the carbide subsystem in rail steel were analyzed in [5][6][7][8][9][10][11][12][13]. The service of rails is accompanied by an appreciable increase in the scalar density of dislocations having attained the value of ≈10*10 10 cm -2 at passed tonnage 1000 mln ton.…”