Effect of Ti content on the microstructure and mechanical behavior of (Fe36Ni18Mn33Al13)100−xTix high entropy alloys

Abstract

a b s t r a c tThe microstructure and mechanical properties studies of a series of two-phase f.c.c./B2 (ordered b.c.c.) lamellar-structured, high entropy alloys (HEA) Fe 36 Ni 18 Mn 33 Al 13 Ti x with x up to 6 at. % Ti have been investigated. X-ray microanalysis in a TEM showed that the Ti resided mostly in the B2 phase. The lamellar spacing decreased significantly with increasing Ti content from 1.56 mm for the undoped alloy to 155 nm with an addition of 4 at. % Ti, leading to a sharp increase in room-temperature yield strength,s y , from 270 MPa to 953 MPa, but with a concomitant decrease in ductility from 22% elongation to 2.3%. Annealing at 1173 K for 20 h greatly increased the lamellar spacing of Fe 36 Ni 18 Mn 33 Al 13 Ti 4 to 577 nm, producing a corresponding decrease in s y to 511 MPa. The yield strengths of all the doped alloys decreased significantly when tensile tested at 973 K with a concomitant increase in ductility due to softening of the B2 phase. The fracture mode changed from cleavage at room temperature to a ductile dimple-type rupture at 973 K. The results are discussed in terms of the Hall-Petch-type relationship.

The effect of carbon on the microstructures, mechanical properties, and deformation mechanisms of thermo-mechanically treated Fe40.4Ni11.3Mn34.8Al7.5Cr6 high entropy alloys

“…3 c and d indicates that the B2 phase is enriched in Ni and Al, while the f.c.c. matrix phase is enriched in Fe, Mn and Cr, which is consistent with the phase equilibria observed in other f.c.c./B2 two-phaseFeNiMnAl alloys[27,28].A BF TEM image of carbides in the 1.1 at. % C-doped HEA cold rolled and annealed at 1273 K for 1 h is shown inFig.…”

Effect of Heat Treatment and Titanium Addition on the Microstructure and Mechanical Properties of Cast Fe31Mn28 Ni15Al24.5Tix High-Entropy Alloys

“…Contrasting the EDX results of the sample without Ti to that containing 3.0 wt.% Ti, some significant differences were observed. Figures 6 and 7 show the maps of the Here, the elemental mapping further confirms the possibility of the presence of all the elements in the solid solutions as previously reported [14,15] and that the lamellar structure diminishes with increasing Ti content. Moreover, coarse grains with some Ti precipitates on the grain boundaries formed with addition of 3.0% Ti.…”

“…From this figure, it can be observed that addition of Ti up to 3.0 wt.% increased significantly the hardness of the alloy from ∼310 to 500 (Hv). According to the explanation of the reported works [14][15][16], the strength of the current alloys are expected to improve because of both solid solution strengthening by Ti addition and by the decrease in the lamellar spacing following the Hall-Petch relationship [19]. Increasing the cooling rate by decreasing the section size down to 5 mm showed little improvement in the hardness.…”

“…In a sole study by Wang et al [14], the effect of Ti addition on the microstructure and strength of Fe 36 Ni 18 Mn 33 Al 13 HEAs was investigated. ey obtained a lamellar microstructure that contains two phases: FCC and B2.…”

Nanostructured multielement (TiHfZrNbVTa)N coatings before and after implantation of N+ ions (1018cm−2): Their structure and mechanical properties

“…Several works have been performed so far to obtain a comprehensive understanding of the effect of constitutive elements on the microstructure, phase composition and mechanical properties of HEA [23][24][25][26][27][28][29][30][31][32][33][34][35][36][37]. Nitride coatings from HEA have received particular attention because of improved physical and mechanical characteristics.…”