Technology of ceramic material siliconborating impact on the properties of protective covering
Journal Title: Вісник Тернопільського національного технічного університету - Year 2015, Vol 78, Issue 2
Abstract
The process of successive saturation of the carbide silicon and disilicide molybdenum reaction-sintered ceramics and properties of protective covering have been investigated. Silicon and boron diffusion saturation was found to provide complete recovery of dioxide silicon and obtaining the protective covering on the material surface. It was found that the silicon saturation can reduce more than twice the content of harmful admixtures in ceramics, silicon dioxide in particular. The saturation of carbide silicon and disilicide molybdenum by silicon reduces the content of harmful admixtures and thereby improves their properties. The main disadvantage of the silicon carbide and disilicide molybdenum products is their low resistance to high temperature oxidization. The method of combination of harmful admixtures under high-temperature treatment and chemical reactions was investigated. The process of carbide silicon and disilicide molybdenum saturation by the non-metallic materials has testified the heaters technological parameters to be improved. The investigation of the heat-resistant covering properties testified, that the hexaboride silicon increases in 2-4 times the ceramics stability under high-temperature sintering and retards undesirable diffusion processes on the covering distribution edge - basis and covering – environment. Carried out investigations make possible to conclude that creation of the protective covering on the surface of the reaction – sintered ceramics materials retards undesirable diffusion process, which occur on the edge basis – silicon-borid covering, and to increase the operating life of the protective layer. Carbide silicon and disilicide molybdenum silicon-boride covering provides complete recovery of the dioxide silicon and creation of the sufficient thickness hexaboride silicon heat-resistant layer on the material surface. The hexaboride silicon layer improves in 2 times the ceramics stability under vacuum annealing and in 4 times in the inert environment, the argon in particular. Creation of the triple phase on the edge covering – environment under siliconborating increases the heat-resistance covering stability and retards the undesirable processes, which occur on the edge hexaboride silicon-ceramics.
Authors and Affiliations
Vasyl Kovbashyn, Ihor Bochar
Keywords
Related Articles
- EP ID EP571471
- DOI -
- Views 38
- Downloads 0
Estimation of influence of residual stresses on fatigue fracture and residual resource of shell structures with a ring welded joint
Geometric inhomogeneities, especially in the firm of pointed crack-like type defects can influence essentially the strength and durability of metal structures. Therefore, detection and measurement of such defects without...
Main principles of «conditional mechanism» design
The article is devoted to the problem of existence of systems of specific spatial mechanisms, which, in contrast to traditional mechanisms intended for putting into motion and moving of various machines or their integral...
Methodology for the experimental research of reinforced cylindrical shell forced oscillations
In the paper the methodology for experimental studies of forced oscillations of a horizontally oriented cylindrical shell which is reinforced from the inside by stringers and bulkheads using the servo-hydraulic test mach...
Contact problem on the wear of the elastic half-plane by canonical form stamps
The problems of contact interaction of the canonical form stamps (cylindrical, elliptical, hyperbolic) with the elastic half-plane taking into account the wastage of material, are solved. The integral equation, based on...
The cargo movement model by the screw conveyor surfaces with the rotating casing
The article defines regularities of the change of the angle parameter of the cargo for the case of slow-moving transport and steady motion for horizontal and hollow inclined conveyors with a rotating casing. This allows...