A cutting tool has one or more sharp cutting edges and is made of a material that is harder than the work material. The cutting edge serves to separate a chip from the parent work material. Connected to the cutting edge are two surfaces of the tool: the rake angle and the flank. The rake face, which directs the flow of the newly formed chip, is oriented at a certain angle called the rake angle. It is measured relative to a plane perpendicular to the work surface. The rake angle can be positive, or negative.
(M. P. Groover, Fundamentals of Modern Manufacturing, p. 484)
Analytical Solid Modeling
The infusing of solid modeling tools for design has been a boon to the designer to describe the part and view the results. For the most part, however, these CAD modelers do not produce an analytical model which is suitable for analysis. Analytic description of the surfaces and volumes are needed so mesh generation algorithms can reliably place nodes on the surface of a model and create nodes internal to the volume. Tighter integration of advanced meshing algorithms with CAD systems is needed with the use of analytical solid modeling. In addition, solid modeling software must become more flexible allowing the solid model detail to be a hction of the type of analysis.
(P.J. Hommert, J. H. Bifffe, The Role of Advanced Engineering Simulation in Model-Based Design, p. 5)
Roll Forming
Rolll forming is a continuous bending process in which opposing rolls are used to produce long sections of formed shapes from coil or strip stock. Several pairs of rolls are usually required to progressively accomplish the bending of stock into the desired shape. Products made by roll forming include channels, gutters, metal siding sections (for homes), pipes and tubing with seams, and various structural sections. Although roll forming has the general appearance of rolling operation (and the tooling certainly looks similar), the difference is that roll forming involves bending rather than compressing the work.
(M. P. Groover, Fundamentals of Modern Manufacturing, p. 470)
Elastic Modulus ( Modulus of Elasticity)
The slope of the stress-strain curve in the elastic region is the modulus of elasticity, E, also known as Young's modulus. The linearity of the stress-strain plot in the elastic region is a graphical statement of Hook's law. The modulus E is a highly practical piece of information. It represents the stiffness of the material, that is, its resistance to elastic strain. This manifests itself as the amount of deformation in normal use below the yield strength and the springiness of the material during forming. As with E, the yield strength has major preactical significance. It shows the resistance of the metal to permanent deformation and indicates the ease with which the metal can be formed by rolling and drawing operations.
(J. F. Shackelford, Introduction to Materials Science for Engineers, pp. 275-276)
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