The Method of Dosed Directional Solidification (DDS) for Casting Turbine Blades
Alexander Stepanovich Verin
Issue:
Volume 5, Issue 1, March 2020
Pages:
1-4
Received:
13 January 2020
Accepted:
17 February 2020
Published:
15 May 2020
Abstract: In this paper it is study a problem of multigrid schemes in two space dimensions and differential operator formula of Laplace and Lagrang for numerical tests, including a composition parameters of microstructures obtained by the DDS method. This technological possibilities of directed crystallization are broad and make it possible to manufacture castings from high- temperature alloys with various sets of properties. The present work is devoted to the possibilities of intensifying directed crystallization of the Ni3Al intermetallic compound by improving of feeding the growth casting, which makes it possible to control the process of structure formation and thus change the properties of material. Directed crystallization of the intermetallic compound is a very complex and unsteady process. This seems to be connected not only with that aluminum segregates in the mother solution that feeds the growing casting but also with the scale factor, i. e., the height of the column of the mother melt and its mold. We can infer from these data that the crystallization conditions in fabricating castings by the developed method are in better equilibrium. These conditions are provided by the dosed feeding of the liquid metal into the casting zone. The alloy obtained by the suggested method has higher mechanical characteristics for temperature ranging from room temperature to 1200°C than metal melted with the use of directed crystallization by the conventional method (CDS).
Abstract: In this paper it is study a problem of multigrid schemes in two space dimensions and differential operator formula of Laplace and Lagrang for numerical tests, including a composition parameters of microstructures obtained by the DDS method. This technological possibilities of directed crystallization are broad and make it possible to manufacture ca...
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Study of Structural and Magnetic Properties for Hybrid Compounds of "X(SrFe12O19) + (1-X) (BiFeO3)"
Pedro Antonio Marinho-Castellanos,
Arles Vega-Garcia,
Julio Cesar Velazquez-Infante,
Yadira Marinho-Del Toro,
Braddy Ivan Jimenez-Morales,
Joaquin Matilla-Arias
Issue:
Volume 5, Issue 1, March 2020
Pages:
5-9
Received:
29 January 2020
Accepted:
10 February 2020
Published:
28 May 2020
Abstract: A structural and magnetic study of the system X(SrFe12O19) + (1-X) (BiFeO3) with X=0, 0.20, 0.40, 0.50, 0.60, 0.80 and 1.0 is presented in this work. The individual phases were obtained by the Sol-Gel method. The powders were mixed by mechanical grinding, then pressed and sintered. Experimental techniques of X-ray diffraction and vibrational magnetometry were used for the characterization of the samples and the Hanawalt method and the Match! Phase Identification from Powder Diffraction were used for the qualitative determination of the phases present in each sample. Rietveld's analysis was carried out with the FullProf Suite-2008 program. The structural results obtained show slight variations of the crystal lattice parameters for both phases and the coexistence of both phases in each sample. The magnetic characterization shows a linear increase of the saturation magnetization, the remanent magnetization and the magnetic anisotropy constant K1, as a function of the concentration of the BiFeO3 and SrFe12O19 phases. A satisfactory congruence is observed between the theoretical predictions and the experimental measurements, an indication that the magnetic parameters reported are due to the superposition, in each compound, of their individual values. Both the XRD pattern and the structural and magnetic characterization show that the two phases coexist individually in the matrix and have a good chemical compatibility between them.
Abstract: A structural and magnetic study of the system X(SrFe12O19) + (1-X) (BiFeO3) with X=0, 0.20, 0.40, 0.50, 0.60, 0.80 and 1.0 is presented in this work. The individual phases were obtained by the Sol-Gel method. The powders were mixed by mechanical grinding, then pressed and sintered. Experimental techniques of X-ray diffraction and vibrational magnet...
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