9624640 Jawahir Cutting tools that provide the correct three dimensional (3-D) chip flow are a way to increase tool life and improve chip handling in machining. Often chip breaking is achieved with a groove on the cutting edge, but a poorly designed groove can cause premature failure of the cutting edge. Designing a 3-D edge geometry for controlling the chip's contact area and flow direction requires a model of the mechanics of chip flow that includes groove geometry. This means that fundamental understanding is needed to achieve the benefits of grooved 3-D tools. This project will investigate 3-D chip flow in machining with complex grooved tools and the geometry changes caused by more than one type of tool wear. The research plan is to: document using high speed film, the mechanics of chip flow, establish a tool failure and grooved tool performance criterion for grooved tools with simultaneous multiple modes of wear, and develop analytical approaches that can be used to design cutting edges for both chip control and tool life. This research will improve the understanding of chip formation and tool wear, by extending the theory from mechanics based on planar faces to 3-D grooved geometry. With this knowledge, cutting tools can be designed without resorting to extensive and time consuming experiments.