Features of the Process Obtaining of Mg-Zn-Y Master Alloy by the Metallothermic Recovery Method of Yttrium Fluoride Melt

At present, magnesium master alloys with such rare earth metals (REM) as yttrium are used in the production of alloys of magnesium and aluminum. These alloys especially the system Mg-6Zn-1Y-0,5Zr are commonly used in the aircraft and automotive industries. The article is devoted to the exploration of the synthesis process features for ternary magnesium master alloys with yttrium and zinc. The authors used X-ray fluorescence analysis (XRF), differential thermal analysis (DTA), and X-ray spectral analysis (XRD). Optical microscopy was used to conduct microstructural studies. The thermal effects that occur during metallothermic reactions of yttrium reduction from the YF3-NaCl-KCl-CaCl2 salt mixture with a melt of magnesium and zinc were investigated, and the temperatures of these effects were determined. It has been confirmed that the metallothermic reaction of yttrium reduction proceeds from the precursors of the composition: Na1.5Y2.5F9, NaYF4, Na5Y9F32, and KY7F22, and starts at a temperature of 471 °C. The results of experimental studies of the process of metallothermic reduction of yttrium from the salt mixture YF3-NaCl-KCl-CaCl2 are presented in detail. These experiments were carried out in a pit furnace at temperatures ranging from 650 to 700 °C, and it was found that, at a synthesis temperature of 700 °C, the yttrium yield is up to 99.1–99.8%. The paper establishes rational technological regimes for the synthesis (temperature 700 °C, exposure for 25 min, the ratio of chlorides to yttrium fluoride 6:1, periodic stirring of the molten metal) at which the yttrium yield reaches up to 99.8%. The structure of the master alloy samples obtained during the experiments was studied. That structure can be distinguished by a uniform distribution of ternary intermetallic compounds (Mg3YZn6) in the bulk of the double magnesium–zinc eutectic. Studies have been carried out on testing the obtained ternary master alloy as an alloying material in the production of alloys of the Mg-6Zn-1Y-0.5Zr system, while the digestibility of yttrium ranged from 91 to 95%

Features of the Process Obtaining of Mg-Zn-Y Master Alloy by the Metallothermic Recovery Method of Yttrium Fluoride Melt

At present, magnesium master alloys with such rare earth metals (REM) as yttrium are used in the production of alloys of magnesium and aluminum. These alloys especially the system Mg-6Zn-1Y-0,5Zr are commonly used in the aircraft and automotive industries. The article is devoted to the exploration of the synthesis process features for ternary magnesium master alloys with yttrium and zinc. The authors used X-ray fluorescence analysis (XRF), differential thermal analysis (DTA), and X-ray spectral analysis (XRD). Optical microscopy was used to conduct microstructural studies. The thermal effects that occur during metallothermic reactions of yttrium reduction from the YF3-NaCl-KCl-CaCl2 salt mixture with a melt of magnesium and zinc were investigated, and the temperatures of these effects were determined. It has been confirmed that the metallothermic reaction of yttrium reduction proceeds from the precursors of the composition: Na1.5Y2.5F9, NaYF4, Na5Y9F32, and KY7F22, and starts at a temperature of 471 °C. The results of experimental studies of the process of metallothermic reduction of yttrium from the salt mixture YF3-NaCl-KCl-CaCl2 are presented in detail. These experiments were carried out in a pit furnace at temperatures ranging from 650 to 700 °C, and it was found that, at a synthesis temperature of 700 °C, the yttrium yield is up to 99.1–99.8%. The paper establishes rational technological regimes for the synthesis (temperature 700 °C, exposure for 25 min, the ratio of chlorides to yttrium fluoride 6:1, periodic stirring of the molten metal) at which the yttrium yield reaches up to 99.8%. The structure of the master alloy samples obtained during the experiments was studied. That structure can be distinguished by a uniform distribution of ternary intermetallic compounds (Mg3YZn6) in the bulk of the double magnesium–zinc eutectic. Studies have been carried out on testing the obtained ternary master alloy as an alloying material in the production of alloys of the Mg-6Zn-1Y-0.5Zr system, while the digestibility of yttrium ranged from 91 to 95%

Research Risk Factors in Monitoring Well Drilling—A Case Study Using Machine Learning Methods

This article takes an approach to creating a machine learning model for the oil and gas industry. This task is dedicated to the most up-to-date issues of machine learning and artificial intelligence. One of the goals of this research was to build a model to predict the possible risks arising in the process of drilling wells. Drilling of wells for oil and gas production is a highly complex and expensive part of reservoir development. Thus, together with injury prevention, there is a goal to save cost expenditures on downtime and repair of drilling equipment. Nowadays, companies have begun to look for ways to improve the efficiency of drilling and minimize non-production time with the help of new technologies. To support decisions in a narrow time frame, it is valuable to have an early warning system. Such a decision support system will help an engineer to intervene in the drilling process and prevent high expenses of unproductive time and equipment repair due to a problem. This work describes a comparison of machine learning algorithms for anomaly detection during well drilling. In particular, machine learning algorithms will make it possible to make decisions when determining the geometry of the grid of wells—the nature of the relative position of production and injection wells at the production facility. Development systems are most often subdivided into the following: placement of wells along a symmetric grid, and placement of wells along a non-symmetric grid (mainly in rows). The tested models classify drilling problems based on historical data from previously drilled wells. To validate anomaly detection algorithms, we used historical logs of drilling problems for 67 wells at a large brownfield in Siberia, Russia. Wells with problems were selected and analyzed. It should be noted that out of the 67 wells, 20 wells were drilled without expenses for unproductive time. The experiential results illustrate that a model based on gradient boosting can classify the complications in the drilling process better than other models

学位論文審査報告

Applications of the Laser Thomson Scattering Method for Measurements of Electron Properties in Reactive Plasmas[Pradoong]Laser Second Harmonic Generation from Monolayer Films at the Air/Water Interface[Slyadneva]Tritium Release Behavior from Irradiated Ceramic Breeder Materials[Beloglazov]Preparation of carbon materials for high performance electric double layer capacitor[喬]Formation of Ordered Mixed Structures Induced by Cooperative Interactions of Two Dissimilar Metal Atoms on a Cu（001）Surface[陳]Study on Compound Choking of Two Subsonic Parallel Flows through a Convergent Duct[權]Experimental Study on Enhanced Boiling Heat Transfer from Silicon-Chips with Micro-PinFins and Submicron-Scale Roughness[魏]Diagnostic and Prognostic Models of Circulation and Material Transport in Suo-Nada, Japan[Rolando]遮熱型ディーゼルエンジンの高温燃焼の制御と多種燃料への適応に関する研究[関山

Assessment Report of Doctoral Theses

Applications of the Laser Thomson Scattering Method for Measurements of Electron Properties in Reactive Plasmas[Pradoong]Laser Second Harmonic Generation from Monolayer Films at the Air/Water Interface[Slyadneva]Tritium Release Behavior from Irradiated Ceramic Breeder Materials[Beloglazov]Preparation of carbon materials for high performance electric double layer capacitor[喬]Formation of Ordered Mixed Structures Induced by Cooperative Interactions of Two Dissimilar Metal Atoms on a Cu（001）Surface[陳]Study on Compound Choking of Two Subsonic Parallel Flows through a Convergent Duct[權]Experimental Study on Enhanced Boiling Heat Transfer from Silicon-Chips with Micro-PinFins and Submicron-Scale Roughness[魏]Diagnostic and Prognostic Models of Circulation and Material Transport in Suo-Nada, Japan[Rolando]遮熱型ディーゼルエンジンの高温燃焼の制御と多種燃料への適応に関する研究[関山