Experience with metal/ceramic coating in stationary gas turbines

1995 ◽  
Vol 76-77 ◽  
pp. 86-94 ◽  
Author(s):  
A.S. Osyka ◽  
A.I. Rybnikov ◽  
S.A. Leontiev ◽  
N.V. Nikitin ◽  
I.S. Malashenko
Author(s):  
Kazuo Takeya ◽  
Hajime Yasui

In 1978, the Japanese government started a national project for energy conservation called the Moonlight Project. The Engineering Research Association for Advanced Gas Turbines was selected to research and develop an advanced gas turbine for this project. The development stages were planned as follows: First, the development of a reheat gas turbine for a pilot plant (AGTJ-100A), and second, a prototype plant (AGTJ-100B). The AGTJ-100A has been undergoing performance tests since 1984 at the Sodegaura Power Station of the Tokyo Electric Power Co., Inc. (TEPCO). The inlet gas temperature of the high pressure turbine (HPT) of the AGTJ-100A is 1573K, while that of the AGTJ-100B is 100K higher. Therefore, various advanced technologies have to be applied to the AGTJ-100B HPT. Ceramic coating on the HPT blades is the most desirable of these technologies. In this paper, the present situation of development, as well as future R & D plans for ceramic coating, is taken into consideration. Steam blade cooling is applied for the IGSC.


Author(s):  
Наталья Витальевна Зайцева ◽  
Жанна Владимировна Вечеркина ◽  
Михаил Анатольевич Крючков ◽  
Виктор Сергеевич Калиниченко ◽  
Николай Валерьевич Морозов ◽  
...  

Вопреки доказанным преимуществам автоматизации зуботехнической лаборатории с помощью компьютерных технологий, изготовление металлокерамическмх несъемных коронок и мостовидных протезов остается востребованным в ортопедической стоматологи видом конструкции. Большой клинический опыт, отработанные технологии, надёжность и относительная простота изготовления дают им неоспоримые положительные качества. И главным моментов, определяющим их качество, долговечность и эффективность заключается в опыте, тандеме работы врача стоматолога-ортопеда и зубного мастера, и конечно же в грамотности выполнения пошаговой последовательности керамического моделирования облицовки выбранной комбинированной конструкции. Изготовление металлокерамических коронок небольшой толщины требует от зубного техника владения различными методиками нанесения керамической облицовки, знаний свойств и особенностей масс мировых производителей, тщательного соблюдения всех этапов и грамотной работы с цветовой палитрой. Создание металлокерамической конструкции предполагает последовательное получение металлического каркаса, на которй в последующем послойно наносят керамическую массу, а затем проводят ее обжиг. Среди технологических операций при создании облицовки цельнолитого металлического каркаса несъемного протеза из металлокерамики следует веделить следующие аспекты: подготовка каркаса протеза, выбор, подготовка и нанесение керамической массы, моделирование и обжиг грунтового слоя, нанесение дентинной массы, этап глазурирования. В научной работе, проведенной сотрудниками кафедры пропедевтической стоматологии ранее, дана характеристика методов моделирования керамической массы, были подробно изложены основные аспекты по обработке керамической массы горячим воздухом, формированию основного слоя керамического покрытия. В последующем, убедившись в высоком качестве грунтового покрытия, переходят к моделированию и обжигу дентинного слоя керамики. В данной статье описана подробная техника нанесения компоненотов керамических масс на опаковой слой керамической массы. Представленный метод трехэтапного нанесения керамического покрытия при изготовлении металлокерамических зубных протезов отвечает всем требованиям моделирования керамики. Следует обратить внимание на точное соблюдение правил послойного нанесения и конденсации керамических масс. Нанесение отдельных слоев керамической массы предполагает наличие опыта у зубного техника Despite the proven advantages of dental laboratory automation using computer technologies, the production of metal-ceramic fixed crowns and bridges remains a popular type of construction in orthopedic dentistry. Extensive clinical experience, proven technologies, reliability and relative ease of manufacture give them undeniable positive qualities. And the main factor that determines their quality, durability and effectiveness is the experience, the tandem work of the dentist-orthopedist and dental master, and of course the literacy of performing a step-by-step sequence of ceramic modeling of the selected combined structure. The production of metal-ceramic crowns of small thickness requires the dental technician to know various methods of applying ceramic cladding, to know the properties and features of the world's leading manufacturers, to carefully observe all stages and to work correctly with the color palette. The creation of a metal-ceramic structure involves the sequential production of a metal frame, on which the ceramic mass is subsequently applied in layers, and then it is fired. Among the technological operations when creating the veneer-cast metal framework removable denture-metal should be wadelite the following aspects: preparation of a denture, the choice, preparation and application of the ceramic mass, the modeling and firing the base coat, applying the dentinal mass, the stage of glazing applications. In the scientific work carried out by the staff of the Department of propaedeutic dentistry earlier, the characteristic of methods for modeling the ceramic mass was given, the main aspects of processing the ceramic mass with hot air, and the formation of the main layer of the ceramic coating were described in detail. After making sure that the high quality of the ground coating is used, they proceed to modeling and firing the dentin layer of ceramics. This article describes a detailed technique for applying ceramic mass components to the opaque layer of the ceramic mass. The presented method of three-stage application of ceramic coating in the manufacture of metal-ceramic dentures meets all the requirements of modeling ceramics. You should pay attention to the exact observance of the rules of layering and condensation of ceramic masses


Author(s):  
Xiaoman Zhang ◽  
Yang Mu ◽  
Shuai Shao ◽  
Collin Wick ◽  
Ramu Ramachandran ◽  
...  

Mechanical failures of interfacial regions of ceramic-coating/metal-adhesion-layer/substrate systems were measured quantitatively and observed concurrently through instrumented microscale mechanical testing in-situ a scanning electron microscope (SEM). Failure of the interfacial regions of coating/interlayer/substrate systems was observed in micro-pillar specimens in-situ under different loading conditions, including shear, compression, and tension. Under shear loading, shear failure of the interfacial region was observed to occur in two stages: an initial uniform shear plastic deformation of the entire metal interlayer followed by an unstable shear-off close to the metal/ceramic interface. Additional testing under compression loading conditions suggests that the unstable shear-off is concomitant with the metal/ceramic interface going from being “locked”, with no relative displacement between materials on the two sides of the interface, to being “unlocked”, with significant relative displacements. Failure of the interfacial region was also observed under tensile loading conditions. Density functional theory (DFT) and molecular dynamics (MD) studies on one particular metal/ceramic interface, namely Ti/TiN, showed that a weak interaction plane exists in the metal layer near the chemical interface in a coherent Ti/TiN structure. Consequently, the free energy and theoretical shear strength of the semi-coherent Ti/TiN interface is found to depend on the physical location of the misfit dislocation network (MDN). The minimum energy and strength of the interface occur when the MDN is near, but not at the chemical interface. The present work gives new insight into the nature of mechanical failure of metal/ceramic interfaces, is relevant to materials-based engineering of metal/ceramic interfaces, and has applications to engineering of ceramic coating/substrate systems.


2013 ◽  
Vol 750-752 ◽  
pp. 2200-2205 ◽  
Author(s):  
Cheng Fan

In this presented work, a coupled thermo-mechanical model is employed to analyze the thermo-mechanical behavior of ceramic functionally graded materials (FGMs) and the crack formation and propagation process of ceramic coating was simulated step in step and step by step using the RFPA (Realistic Failure Process Analysis) 2D-Thermo code. The thermal shock fracture behavior is discussed based on the basis of the simulated crack morphology and elucidated the mechanism of crack deformation and crack propagation. The state change from compression to tension whose magnitude is large enough to exceed the tension strength of ceramic causes the vertical crack. The numerical results agreed well with the experimental results in the previous literature.


2013 ◽  
Vol 341-342 ◽  
pp. 83-87
Author(s):  
Ling Xiao Zhu ◽  
Jian Jun Hao ◽  
Liang Gao ◽  
Yue Jin Ma ◽  
Jian Guo Zhao

The metal ceramic coating of TiAl (CN) by nitrogen-arc cladding technology was produced on the surface of 45#steel.The phase composition of coating was analyzed with X-ray diffractometer; The bonding state and microstructure were observed with scanning electron microscope; The microhardness was examined and the wear resistance of the metal ceramic coating compared with that of 60Si2Mn steel treated by quenching and tempering was tested by abrasive tester as well. The results indicated that the TiAl (CN) ceramic particle synthesized in-situ is distributed dispersively in the cladding and the size is under 3 um. The excellent bonding between the coating and 45# steel substrate is strengthened by the strong metallurgical interface; the coating is uniform and continuous. The maximum microhardness of cladding is HV0.21820 and the abrasive performance is better than 60Si2Mn steel treated by quenching and tempering. The simulation test results showed that the cladding is good, and can be used to the repair and remanufacture for wearable parts of stubble-cleaning cutter.


2021 ◽  
Vol 2131 (5) ◽  
pp. 052028
Author(s):  
P Batkhuu ◽  
G Omoontsoo ◽  
B Lygdenov ◽  
A Guriev

Abstract Mechanical properties, such as wear-resistance and hardness, of laser welded and cladded high chromium white iron were investigated. The study involves the laser welding, cladding, and laser surface melt treatment by 3-kW Nd:YAG continuous wave high power laser. The laser welding of 2-mm thick high chromium white iron samples was laser welded in two combinations: iron-to-iron and iron-to-steel. Strong metallurgical bonding was witnessed between not only the iron samples but also iron and steel samples by laser welding. Three types of powder materials were used to laser clad the samples: metal-ceramic (compositionally close to INCO-702), stellite-21, and stellite-1 in order to estimate mechanical property changes and process ability of high chromium white iron. Even though the microstructure of metal-ceramic coating shows worse than stellite powder coatings it has more hardness and wear resistant property which were comparable to base iron. Hardness of metal-ceramic coating was slightly lower than base iron, yet the wear resistance was increased twofold.


Author(s):  
Kazuo Uchida ◽  
Akinori Koga ◽  
Kiyomi Teshima ◽  
Masashi Arai

In 1978, the Japanese government started a national project for energy conservation called the Moonlight Project. The Engineering Research Association for Advanced Gas Turbines was selected to research and develop an advanced gas turbine for this project. The development stages were planned as follows: First, the development of a reheat gas turbine for a pilot plant (AGTJ-100A), and second, a prototype plant (AGTJ-100B). The AGTJ-100A has been undergoing performance tests since 1984 at the Sodegaura Power Station of the Tokyo Electric Power Co., Inc. (TEPCO). The inlet gas temperature of the high pressure turbine (HPT) of the AGTJ-100A is 1573K, while that of the AGTJ-100B is 100K higher. Therefore, various advanced technologies have to be applied to the AGTJ-100B HPT. Ceramic coating on the HPT blades is the most desirable of these technologies. In this paper, the present situation of development, as well as future R & D plans for ceramic coating will be described.


2014 ◽  
Vol 85 ◽  
pp. 332-339 ◽  
Author(s):  
Jing Ji ◽  
Jianqiu Zhou ◽  
Xuming Pang ◽  
Shuhong Dong ◽  
Ruiqin Hu ◽  
...  

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