CUTTING-TOOL RELIABILITY-ANALYSIS FOR VARIABLE FEED MILLING OF 17-4PHSTAINLESS-STEEL

Variable feed machining has recently been proposed as a significant me thod to improve cutting tool life particularly for hard and difficult to machine materials. This method, which is easy to apply in industry, has been shown to improve tool life in the order of 40% in certain ca ses. This paper presents a reliability model for the quantitative stud y of the effect of feed variation on tool wear and tool life. To bette r compare processes with two different wear modes, a reliability model taking simultaneously into account both flank and face wear has been developed. With this model, which is based on experiments, the tool li fe for the constant and variable feed cases was calculated from the re liability function. The mean time to failure, obtained from the reliab ility function, provides an accurate evaluation for any probabilistic distribution. The proposed method is therefore a general approach that can be used for analyzing cutting tool life under any conditions and for any equipment and material.