Wyniki 1-1 spośród 1 dla zapytania: authorDesc:"Aleksandra Dubiel"

The impact of TiN content on microstructure and mechanical properties of ceramic particulate composite Si3N4-TiN DOI:10.15199/28.2017.5.4

  1. INTRODUCTION Particulate ceramic composites are multiphase materials wherein particles of one phase are dispersed in a second phase of the polycrystalline matrix. The creation of such family of materials is based on the concept of connection of two different phases with suitable values of the coefficients of thermal expansion to induce internal stresses which influence the propagation of cracks in the material (for example by a crack deflection mechanism) and thus its mechanical properties [1, 2]. Appropriate selection of the composite phases and composite microstructure are factors which influence the strength and fracture toughness of ceramic composite [3, 4]. Volume fraction of the dispersed phase, size and shape of dispersed particles and the way of their distribution in the matrix are important variables of particulate composites microstructure [5]. Quantitative description of the microstructure of the material is based on the characterization of the material with the stereological parameters [6]. Determination of the stereological parameters require processing of the material microstructure images and performing measurements on them [7, 8]. This is done with the help of a computer program for image analysis. The silicon nitride Si3N4 is one of the basic structural ceramic materials because its high flexural strength, high fracture toughness, high hardness and excellent wear resistance. Various types of composites with a matrix of Si3N4 have been developed in order to improve the mechanical properties of silicon nitride ceramics: laminates and composites with oriented reinforcement phase [9÷12] or particulate composites [13, 14]. One material of latter group is the Si3N4-TiN particulate composite [14]. Titanium nitride has good physical properties (high melting point, high electrical conductivity, hardness and strength) and good resistance to erosion and corrosion making it suitable reinforcement phase [15, 16]. The th[...]

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