Survival Life Analysis of the Cutting Tools During Turning Titanium Metal Matrix Composites (Ti-MMCs)

Metal matrix composites (MMCs), as a new generation of materials; have proven to be viable materials in various industrial fields such as biomedical and aerospace. In order to achieve a valuable modification in various properties of materials, metallic matrices are reinforced with additional phases based on the chemical and/or physical properties required in the in-service operating conditions. The presence of the reinforcements in MMCs improves the physical, mechanical and thermal properties of the composite; however it induces significant issues in the domain of machining, such as high tool wear and inferior surface finish. The interaction between the tool and abrasive hard reinforcing particles induces complex deformation behaviour in the MMC structure. Sever tool wear is technically the most important drawback of machining MMCs.In this study a statistical model is developed to estimate the mean residual life (MRL) of the cutting tool during machining Ti-MMCs. Initial wear, steady wear and rapid wear regions in the tool wear curve are regarded as the different states in the statistical model. Hence, the valuable information regarding the estimated total time spent in each state, called the sojourn time, and the transition times between the states are obtained from the model.In this paper the standard cutting conditions, based on the recommendation of the tool supplier, are adopted. Based on a Weibull model, the reliability and hazard functions are obtained and are utilized in order to calculate the MRL and the sojourn times.