Experimental and Calculation Analysis of the Behavior of Titanium Diboride-Boron Carbide Cermet under Impact Loading

Abstract

The transition to a new generation of materials operating under intense dynamic loads (impact, explosion) requires constructional materials whose strength, hardness, and fracture viscosity exceed the typical values.The fundamental advantages of ceramic materials over metals are their better performance characteristics (refractoriness, hardness, wear resistance, corrosion resistance, insulating properties, etc.) and the possibility of controlling their functional and design properties (density, strength, viscosity, etc.) over wide ranges during the production of the materials. However, under high-velocity impact, the ceramic materials based on refractory compounds are brittle and unreliable. The high-hardness ceramics contain a large number of stress concentrators (grain boundaries, cracks, pores, etc.) at which fracture nucleation is activated even in the region of elastic deformation of material. Microfractures in such materials can arise in compression under the action of deviator stresses. With an increase in the load pulse intensity, the number of microfractures in the compression stage rises sharply, which further results in a decrease in the tensile strength [1].A promising method for improving the physicomechanical properties of ceramics operating at high pressures and temperatures is to introduce an efficient metallic binder into them. The increased adhesiveness of the metal matrix and the ceramic component can be reached by producing cermet by self-propagating hightemperature synthesis under the application of pressure to the synthesis product [2,3]. Deformation compacting of the synthesis product heated by the chemical reaction opens the way to creating radically new materials with a high-hardness ceramic component. Although the physicochemical and technological principles of production of such materials are generally indicated and much has already been done, their practical implementation in each particular case requires much effort in science and technology. Analysis of the exothermicity of a number of powder mixtures based on TiC, TiB 2 , etc., showed [4] that the heat released is sufficient to produce a wide range of composites since, in the reaction mixture, the melting point of the additionally introduced filler can be reached and conditions of intense heat and mass transfer between the reagents can be created. The combination of high (up to 3000 ° C) temperatures and increased pressures in the contact zones of interfacial interaction sufficiently ensures the required adhesive properties, which is not always achieved by conventional methods for sintering powder materials. Combinations of process schemes with variation of imposed loads allow one to obtain, by selfpropagating high-temperature synthesis, both monolithic and porous cermets based on complex nonoxide ceramics. A cermet based on TiB 2 and B 4 C was obtained by this procedure.CERTAIN PROPERTIES OF TIB 2 -B 4 C CERMET Figure 1 presents the microstructure of the TiB 2 -B 4 C cermet. Against the background of the light-colored metal componen...

Synthesis, structure, and properties of polymer‐derived, metal‐reinforced boron carbide cermet composites

“…Metal‐reinforced ceramic composites, which are also known as cermets, incorporate 10–30 wt.% metal or ceramic inclusions into the presintered greenbodies and rely on similar hot‐press sintering approaches to densify the resulting composites 23 . Many cermet B 4 C matrix composites have been reported, 24 including titanium, 25 copper, 26 and aluminum‐reinforced refractory carbides 27 . These incorporations facilitate structural ductility, resist fractures, plastic deformation, and material creep 28 .…”

Разработка И Исследование Двуслойного Металлокерамического Материала Для Защитных Преград В Условиях Высокоскоростного Удара

“…Повышенное внимание исследователей уделяется изучению функциональных свойств многокомпонентных металлокерамических материалов (слоистых, градиентных, наноструктурированных и др.) в условиях высокоэнергетического воздействия [2,3] и поиска путей достижения необходимой ударной стойкости защитных конструкций.…”