Production Of Amorphous Alloys Research Articles

Pressure Prediction Model in Transition Ladle based on Adaptive PSO-BP Neural Network

Generally, the pressure in the transition ladle during the manufacturing of amorphous alloys could be influenced by numerous factors. Given these issues, BP neural network is employed in this paper to ensure the prediction of the pressure in the transition ladle in the production of amorphous alloys, and adaptive PSO is adopted to adjust the weights and thresholds. The particle swarm is adaptively divided by the median value, the best location is searched locally, and the flight direction and speed of each particle are adjusted to obtain good results. Finally, emulations are performed using the amorphous alloy production site data of a steel plant. The results demonstrate that the pressure prediction model has higher prediction precision in the transition ladle established by the adaptive PSO-BP neural network. This can lay a foundation for the latter pressure control settings in the transition ladle.

Production of Amorphous Alloys by Special Electrometallurgy Methods

ABSTRACTFast-quenched alloys with amorphous and microcrystalline structures were obtained by the cooling drum spinning method during plasma-arc melting process. Thermal load measurements carried out during the melting process and the spinning of the molten material that followed, helped us to modify the existing plasma-arc equipment. Metallographic analyses of the amorphous alloys showed the influence of some quenching process parameters on the creation of their microstructure and revealed the nature of the formation of the crystal structures.

Design of coolant disks for the production of amorphous alloys

The thermal operating conditions of coolant disks (without internal cooling) for the production of amorphous and microcrystalline strip are analyzed. The thermal balance conditions of the disk are calculated in producing strip of different width, at different melt flow rates. It is established that such disks may be used in small machines with the casting of 2 kg of metal per working cycle. To increase the mass of cast metal and the strip width, the disk diameter or the working surface area must be increased, while the melt flow rate from the nozzle and the disk speed must be reduced.

Investigation of Amorphous/Crystalline State in Cu-Hf-Al Alloys

Cu-Hf-Al alloys are considered to be relatively new ones among Cu-based bulk amorphous alloys. Cu-Hf-Al alloys have high strength in amorphous state and this property makes many applications feasible for the industry. During the production of amorphous alloys the most important purpose is to produce them in the biggest diameter to make them suitable for a wide range of applications. The circumstances of the production process have a great influence on the developing structure. In the present work solidification of Cu-Hf-Al alloys were investigated. The alloys were cast into different shapes with different Al contents with special regard to the appearance of the amorphous/crystalline structure. The appearance and the structure of crystalline phases were determined by X-ray diffraction and X-ray, DSC and metallographic measurements were used to investigate the developing structure.

Experience in using zirconia refractories in linings of furnaces for the production of amorphous alloys

The structure of a two-layer lining of a melting chamber with a functional zirconia-based layer and a nonfunctional periclase layer is described. The lining has been tested in service and installed in Sirius industrial installations. It proved to have high endurance in service and ensured reliable operation of an induction furnace and the requisite purity of amorphous alloys.

Irradiation-induced softening of Ni3P and (Ni,Fe,Cr)3P alloys

Production of amorphous alloys by solid state reactions (SSR) has attracted much interest during the last few years. One of the methods to induce such a reaction is the irradiation of suitable crystalline alloys by fast particles. Examination of this kind of SSR in M[sub 3]P type of brazing alloys (M: Metal) is attractive because of the following reason: In brazed joints of candidate structural materials like 316L stainless steel for applications in fusion reactors, crystalline intermetallic phases have been detected which are unstable relative to the amorphous state when irradiated at moderate temperatures with fast particles. It is expected that the transition to the amorphous state is accompanied by changes of the mechanical properties, which are of fundamental interest in this context. Until now, only a few studies on the evolution of mechanical properties during amorphization have been performed. Measurements of microhardness of the crystalline and the corresponding amorphous phase do not exist to the authors knowledge. In this communication, the authors present results on changes of microhardness, due to amorphization by fast ions. The measurements have been performed on a model alloy Ni[sub 3]P and on the brazed joint of stainless steel 316L, containing M[sub 3]P (M: Ni,more » Fe, Cr) as one of the phases. Though microhardness is not a fundamental property of materials, it is a manifestation of several related properties, such as yield stress, ductility, work-hardening, elastic modulus and residual stress states. It represents a resistance for indentation and is, therefore, appropriate for comparative purposes.« less