Abstract:
The possibility of synthesizing metal ceramics from a powder and granulated mixture of (100 - X)(Ti + C) + X Me, X = 0 $\div$ 30% (wt.), was tested by replacing nichrome Me = X20H80 with a mixture of Ni and Cr metal powders for granules of 0.6 and 1.7 mm in size. The experiments were carried out with impurity gases filtered in the direction of the combustion front or removed through the side surface of the sample. Quantitative estimates of the impurity gas content in the studied mixtures were obtained, which satisfactorily explained the experimental combustion rate of the granulated mixtures. The calculation results showed that a safe conductive combustion mode was observed for all compositions with 0.6 mm granules. For a batch of 1.7 mm granules, combustion occurred in the convective mode at X$<$ 10% (a bundle of Ni and Cr) and at X$<$ 20% (a bundle of nichrome). The results of X-ray phase analysis showed the identity of the phase composition of combustion products when replacing nichrome powder with a mixture of Ni and Cr powders with the same dilution with a metal binder X and the absence of side phases.
Keywords:SHS, titanium carbide, nichrome, metal ceramics, powder mixtures, granules, impurity gas evolution.