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The conventional pyrometallurgical method for separating lead–antimony alloy produced from jamesonite has a lot of imperfections such as long-term process, tremendous energy cost and harm to the environment. Therefore, a new method to separate lead and antimony from lead–antimony alloy by fractional crystallization is investigated. The experimental results demonstrate that the lead content decreases with the increase of length to the metal column’s bottom. Lead content of the bottom can reach larger than 80% by weight after lifting. In the experimental speed range, the lifting speed has very small impact on the separation effect. After 4 times’ lifting, crude lead bullion (larger than 83% by weight) whose lead content is close to the eutectic point of lead–antimony binary system is gained in the bottom and the antimony can be used for further refining process without converting into Sb 2 O 3 . The separating efficiency of lead in the bottom has reached the theoretical level of fractional crystallization for lead–antimony alloy containing about 40% by weight antimony. [ABSTRACT FROM AUTHOR]

In order to gain insight into how the addition of Cu element affects the crystallization mechanism of amorphous nanocrystalline alloys and soft magnetic properties, the crystallization behavior of (Fe 0.83 B 0.11 Si 0.02 P 0.03 C 0.01) 100-x Cu x (x = 0 and 0.5) amorphous ribbons was investigated based on kinetic and thermodynamic behavior under non-isothermal and isothermal annealing conditions. The results show that under non-isothermal annealing conditions, the Cu0.5 amorphous ribbon not only favors the formation of the amorphous structure, but also enlarges the temperature window for annealing and improves the thermal stability of the α-Fe(Si) phase. At the same time, the Cu0.5 amorphous ribbon shows slow kinetic and is insensitive to heating rate change during annealing treatment. Under isothermal conditions, the addition of Cu decreases the nucleation activation energy (E n) and increases the growth activation energy (E g). This further indicates that the nucleation of α-Fe(Si) grains is easier than the growth process, which is conducive to the formation of a homogeneous nanostructure and improves the soft magnetic properties of the alloy. Compared to Cu0 amorphous ribbon, it is also shown that the Cu0.5 amorphous ribbon changes the crystallization mechanism from diffusion-controlled one-dimensional to two-dimensional growth when the crystallization volume fraction x is 10–30 vol%. While three-dimensional growth become dominated when x is reaches 60 vol% for both ribbons. Therefore, the kinetics of crystallization as well as microstructure supports that the Cu0.5 ribbon is able to exhibit uniformly fine nanocrystalline structures. Further, the Cu0.5 nanocrystalline ribbon shows a higher B s of 1.85 T and a lower H c of 2.55 A/m, respectively, and the favorable (100) orientation of α-Fe(Si) grains formed after annealing is another factor to increase B s. • The Cu-containing alloy show kinetic insensitivity and is suitable for a high heating rate. • The addition of Cu changes the crystallization mechanism when x is between 10% and 30%. • When the applied magnetic field is ND, precipitation of (100) orientation α-Fe grains favors enhancing B s. • The Cu0.5 alloy show B s of 1.85 T, H c of 2.55 A/m. [ABSTRACT FROM AUTHOR]

Effects of Fe content on magnetic properties and bending ductility of FeSiBPC amorphous alloy ribbons before and after annealing were systematically investigated. It was found that all alloys had high amorphous forming ability and good soft magnetic properties after annealing. The transition temperature of bending ductility-brittleness decreases much faster than that of soft magnetic properties with the increase of Fe content. It is interesting that alloys with Fe content higher than 80 at.% exhibit good ductility before and after annealing at the optimal condition. The alloy with Fe content of 71 at.% is brittle even at as-spun state. The saturation flux density ( B s ) and coercivity ( H c ) decrease with decrease of the Fe content and deviate from a linear fitting tendency. The temperature asynchronism between magnetic properties and bending ductility of amorphous alloy ribbons was discussed. This work will bring a new perspective to study the annealing induced brittleness and a guidance for the future development of the amorphous alloys. [ABSTRACT FROM AUTHOR]

In the present investigation, the glass forming ability (GFA), thermal stability, and soft magnetic properties of Fe 85 Si 6- x B 8 Cu 1 C x alloys are investigated by the substitution of C for Si. It was found that the GFA of C-containing alloys is remarkably enhanced when a certain amount of Si is replaced by C in a C-free alloy. The temperature interval between the first and second crystallization temperatures is also improved by C addition and reaches a maximum value of 169 °C for the as-spun Fe 85 Si 2 B 8 Cu 1 C 4 amorphous alloy. The Fe 85 Si 4 B 8 Cu 1 C 2 nanocrystalline alloy exhibits the best soft magnetic properties with the highest saturation magnetic flux density (B s) of 1.95 T and the lowest coercivity (H c) of 4.1 A/m, which corresponds to the highest grain number density (N d). The high GFA, large annealing window, low cost, and excellent soft magnetic properties enable the Fe 85 Si 2 B 8 Cu 1 C 4 nanocrystalline alloy as a material with wide applicability. Moreover, this work is highly beneficial in balancing the relationship between a high B s and sufficient GFA in the production of Fe-rich nanocrystalline alloys. • Adding C to Fe-Si-B-C-Cu alloys can improve both the GFA and thermal stability of the as-spun amorphous alloy ribbons. • Addition of appropriate amount of C to Fe-Si-B-C-Cu amorphous alloys can enhance their soft magnetic properties. • As-annealed Fe 85 Si 4 B 8 Cu 1 C 2 alloy exhibits a high B s of 1.95 T and low H c of 4.1 A/m. [ABSTRACT FROM AUTHOR]

• The phase constituents of Al x CrFeNi MEAs can be significantly adjusted by tuning x within narrow region between 0.3 and 0.4. • A novel microstructure consisted of FCC distributed on the grain boundaries of BCC phase was found for the Al 0.37 CrFeNi MEA. • The Al 0.37 CrFeNi MEA shows higher damping capacity of 0.07093 and comprehensive compression properties. In this paper, the phase constituent, damping and compressive properties of as-cast Al x CrFeNi (x = 0.3, 0.35, 0.37, 0.4, 0.5) medium entropy alloys (MEAs) were studied. The results show that the phase constituent changes gradually from a face-centered cubic (FCC) dominated structure to a single body-centered cubic (BCC) structure when x increases from 0.3 to 0.5. A novel mesh microstructure consisted of 88.3 vol% BCC phase as the hard matrix and 11.7 vol% FCC structure as the secondary soft phase was screened out by pinpointing x of 0.37. The combination of hard matrix and soft secondary phase results in a very high damping capacity up to 0.07093 for such Al 0.37 CrFeNi MEA at the corresponding strain amplitude of 1.5 × 10−4. Both the grain size of the BCC phase and the grain boundaries where the FCC phase is distributed are important to increase the damping capacity of the MEA. The excellent damping performance and comprehensive mechanical properties indicate that the Al 0.37 CrFeNi MEA has potential application as a damping material. [ABSTRACT FROM AUTHOR]