Structure of a W-enriched phase in Fe–Co–Cr–W–Ga alloys

High-strength magnetically hard Fe-Cr-Co-Based alloys with reduced content of chromium and cobalt

“…Figure 3 demonstrates the Mössbauer spectrum and a three core distribution of probability density of hyperfine fields Р(Н) and quadrupole splitting Р(Q) for a speci men of the Fe-15Cr-13Co-8W-0.5Ga alloy after treatment for optimum properties (here, Н is the hyperfine magnetic field, and Q is the quadrupole split ting). In addition, as in the case of the alloys with 22% Cr and 15% Co [20], it is possible to separate three regions, one of which corresponds to high values of hyperfine field (chromium depleted strongly magnetic α 1 phase), another corresponds to low values of the hyperfine field (weakly magnetic α 2 phase enriched in chromium), and the third region is a paramagnetic dou blet shifted relative to zero as a result of quadrupole split ting (according to earlier studies [20,23], the paramag netic doublet corresponds to a tungsten rich phase). Figure 4 illustrates the distribution functions of probability density Р(Н) and Р(Q) for three specimens with various contents of Cr and Co (the data for the Fe-22Cr-15Co-9W-0.5Ga alloy were published earlier in [20]).…”

“…The same situation was observed earlier in the Fe-22Cr-15Co-9W-0.5Ga alloy. After low temperature aging, the X ray diffraction patterns contained very broad lines of a solid solution based on α Fe with a lattice parameter of 0.2871-0.2869 nm and very weak lines of a phase which previously [20,23] was determined as a tungsten rich η' phase. Note that the lattice parameter of the α phase in the alloys studied in this work is sig nificantly lower than that in the alloys with 22% Cr and 15% Co (about 0.2875 nm [20]).…”

The role of plastic deformation in the creation of high strength in hard magnetic alloys Fe-Cr-Co-W-Ga

“…In both cases, three regions can be separated in the curves given in Fig. 2b; one of them corresponds to high val ues of the HFF (according to the discussion of Möss bauer studies in [2], this is chromium depleted strongly magnetic phase α 1 ); another phase, to low values of HFF (chromium rich weakly magnetic α 2 phase); and the third is represented by a paramag netic doublet shifted with respect to zero as a result of Influence of the degree of deformation preceding aging on the magnetic and mechanical properties of the Fe-Cr-Co-WGa alloy Content of elements ε (%) Magnetic properties Mechanical properties the existence of quadrupole splitting (according to [2,3], it corresponds to the tungsten enriched η' phase). It can be seen that the decrease in the chro mium concentration from 22 to 15% leads to a change in the peak intensities in the high field portion of the Р(Н) distribution whereas the intensity of the low field portion decreases and the intensity of the paramagnetic doublet increases slightly.…”

Fe–15 wt-Cr–X wt-C hardfacing surface layer: Wear resistance and its enhanced mechanism with C additive

“…[7][8][9] In order to obtain more excellent performance of the Fe-Cr-C alloy workpieces after hardfacing, the composition of the hardfacing surface layer should be optimised, so as to improve its microstructure and property. 3,[10][11][12][13][14][15][16] Previous researches indicated that, in the Fe-Cr-C alloy, element Ti can refine the primary M 7 C 3 carbide, so as to improve its wear resistance. 3,11,12 Element W can increase tempering resistance and red hardness, which ensure workpieces with high hardness and wear resistance at high temperatures.…”

“…3,11,12 Element W can increase tempering resistance and red hardness, which ensure workpieces with high hardness and wear resistance at high temperatures. 13,14 Element V not only refines the matrix microstructure, to improve the toughness of the Fe-Cr-C alloy, but also combine with C to form VC, to increase the hardness and wear resistance of the hardfacing surface layer. [15][16][17] However, in all kinds of elements, the influence of element C on the microstructure and property of the Fe-Cr-C alloy is the most significant.…”