An experimental investigation of chatter effects on tool life

Tool wear is one of the most important considerations in machining operations, as it affects surface quality and integrity, productivity, and cost. The most commonly used model for tool life analysis is the one proposed by F. W. Taylor about a century ago. Although the extended form of this equation includes the effects of important cutting conditions on tool wear, tool life studies are mostly performed under stable cutting conditions where the effect of chatter vibrations are not considered. This paper presents an empirical attempt to understand tool life under vibratory cutting conditions. Tool wear data are collected in turning and milling on different work materials under stable and chatter conditions. The effects of cutting conditions as well as severity of chatter on tool life are analysed. The results indicate significant reduction in tool life on account of chatter, as expected. They also show that the severity of chatter, and thus the vibration amplitude, greatly reduce the life of cutting tools. These results can be useful in evaluating the real cost of chatter by including the reduced tool life. They can also be useful in justifying the cost of chatter suppression and more rigid machining systems.