The influence of TiB2 content on high temperature flexural strength and reliability of the developed titanium carbonitride based ceramic tool material

Abstract

n this study, the influence of TiB2 content on flexural strength and reliability of the developed Titanium carbonitride based ceramic tool materials at high temperature was investigated. It was found that the flexural strength of Titanium carbonitride based ceramic tool materials (TB30TW) with 30 wt% TiB2 content was 1.49 times that of Titanium carbonitride based ceramic tool materials (TB20TW) with 20 wt% TiB2 content at room temperature. However, when the temperature exceeded 800 °C, the flexural strength of the two composites tended to be similar. The flexural strength of the TB30TW with higher TiB2 content dropped greatly at high temperature ascribed the oxidation behavior of TiB2. The distribution of measured high temperature flexural strength for TB30TW at 800 °C could well obey a Weibull distribution function, which was consistent with TB20TW. The Weibull distribution shape parameter of the flexural strength of TB30TW was higher than that of TB20TW at 800 °C, then the distribution of the high temperature flexural strength of TB30TW was less discrete than that of TB20TW. The results can serve as reference in the design composite ceramic tool materials and help to evaluate cutting reliability of ceramic cutting tools.