Effect of carbon on the sinterability of highly dispersed powders corresponding to the TiN-TiC section of the titanium-carbon-nigrogen system and the properties of the specimens made from them

Abstract

Titanium carbide, nitride, and carbonitrides form the components of a number of highrefractory materials and protective coatings. In order to ensure their proper application, it is necessary to evaluate their physicochemical properties such as hardness, the modulus of elasticity, Poisson's ratio, and the ultimate bend strength which determine the service characteristics of the refractories and their correlation with the sintering parameters. In view of this, we studied the effect of carbon on the sinterability during hot pressing and the properties of the specimens made from ultrafine (highly dispersed) powders of titanium carbonitrides (as compared to those of the specimens made from titanium nitride); the investigated characteristics included density Pm, porosity P, hardness HRA, the speed of longitudinal ultrasonic waves Cs Poisson's ratio v, the modulus of normal elasticity E, the shear modulus G, and the ultimate bend strength Obn d.

Synthesis of nanocrystalline titanium carbonitride during milling of titanium and carbon in nitrogen atmosphere

“…Recently, several investigations have reported that Ti(C,N) nano-powder can be used as an inoculant to refine the microstructure of castings [2][3][4]. Conventional methods to synthesize Ti(C,N) powders are classified as follows: (1) solid state methods, such as chemical reduction of titanium oxide, titanium chloride, or titanium hydride by carbon, nitrogen, and ammonia [5,6]; direct reaction of TiC with TiN or Ti with C, N 2 [7][8][9][10][11][12]; selfpropagating high-temperature synthesis [13][14][15][16][17]; (2) gaseous state methods, such as chemical vapor deposition process [18]; (3) liquid state methods, such as thermal decomposition process [19]. All of these methods need a complex manipulation and/or high temperatures.…”