Abstract: A method of determining expected fatigue life of machined bearing races or other components wherein a hardened surface of each bearing race is machined to provide a machined surface including the steps of determining hardness distribution and residual stress distribution along a depth into the machined surface as a function of cutting parameters, determining a relationship of expected fatigue life of the machined bearing races as a function of the hardness distribution and the residual stress distribution using a fracture mechanics model, and determining expected fatigue life from the relationship using actual cutting parameters employed in machining the hardened surface of the bearing races. Cutting conditions to optimize fatigue life can be selected based on the expected fatigue life.

Abstract: A method of determining expected fatigue life of machined bearing races or other components wherein a hardened surface of each bearing race is machined to provide a machined surface including the steps of determining hardness distribution and residual stress distribution along a depth into the machined surface as a function of cutting parameters, determining a relationship of expected fatigue life of the machined bearing races as a function of the hardness distribution and the residual stress distribution using a fracture mechanics model, and determining expected fatigue life from the relationship using actual cutting parameters employed in machining the hardened surface of the bearing races. Cutting conditions to optimize fatigue life can be selected based on the expected fatigue life.

Abstract: A cutting tool for metallic or other non-wood materials is provided having a tool body with a leading cutting edge for making a first roughing cut on a workpiece and having a second trailing cutting edge so arranged on the same tool body relative to the first cutting edge that the second cutting edge makes a second finishing cut of the workpiece to provide final dimensions and surface integrity when the workpiece and the cutting tool are relatively moved to engage the cutting tool and workpiece. For a cutting tool comprising a drill, the leading cutting edge cuts a smaller diameter hole than the trailing cutting edge. For a cutting tool comprising a turning or milling tool, the leading cutting edge cuts a larger diameter surface on the workpiece than the trailingcutting edge. Also provided is a drill having a leading end provided with multiple cutting tips spaced laterally apart on the leading end in a manner to reduce deflection of the drill and produce a straighter hole in a workpiece.

Abstract: A process for manufacturing a component on which in-service stresses are imposed by in-service loading conditions. The process generally entails fabricating the component such that residual stresses are induced in the component that substantially offset one or more primary stresses which would otherwise limit the maximum service life of the component. The residual stresses are induced by creating compressive stresses in the component that extend sufficiently beneath the working surface of the component during fabrication. In order to appropriately attain the necessary residual stresses, the process of this invention includes developing a model of the component, and then applying the in-service loading conditions to the model to determine the in-service stresses on the component. Thereafter, at least one of the in-service stresses is identified as being critical, i.e., a stress that establishes the maximum service life of the component.

Abstract: A method and apparatus for machining a workpiece to perform several functions including sensing tool wear, enhancing tool life, tool wear compensation, cutting a workpiece having two different materials joined at a boundry, and suppressing chatter, including placing a cutting tool having a rake face and a clearance face with a first clearance angle with respect to a workpiece and a second clearance face with a second clearance angle with respect thereto and with the first clearance angle being less than the second clearance angle and supporting the cutting tool in a rotatable tool holder having an axis of rotation with the cutting tool tip being aligned with the axis of rotation such that rotation of the holder varies the cutting tool geometry to perform the several functions.

Abstract: A tool holder constituting an adaptive machining control system to automatically manipulate tool rake angle using in-process force feedback. The tool holder includes a rotatable member for holding a cutting member which cuts a workpiece, a motor to rotate the holding member, and a sensor and control logic to sense cutting forces and activate the motor to rotate the holding member and change the tool rake angle. The cutting member is held so that it rotates about an axis through its cutting tip to change the rake angle without varying the depth of cut on the workpiece. In an alternative embodiment, a manually operated tool holder is manipulated to similarly rotate a cutting member to vary the rake angle.