6Machined SurfacesFIGURE 35-3 (a) Terminology used in specifying and measuring surface quality; (b) symbols used on drawingby part designers, with definitions of symbols; (c) lay symbols; (d) lay symbols applied on drawings.
7Surface MeasurementFIGURE 35-4 (a) Schematic of stylus profile device for measuring surface roughness and surfaceprofile with two readout devices shown: a meter for AA or rms values and a strip chart recorder forsurface profile. (b) Profile enlarged. (c) Examples of surface profiles.
8Surface Finish Measurement FIGURE 35-5 Typical machinedsteel surface as created by facemilling and examined in the SEM. Amicrograph (same magnification) ofa in. stylus tip has beensuperimposed at the top.
9SEM Micrograph FIGURE 35-6 (a) SEM micrograph of a U.S. dime, showing the S in the wordTRUST after the region has beentraced by a stylus-type machine.(b) Topographical map of the Sregion of the word TRUST from aU.S. dime [compare to part (a)].
10RoughnessFIGURE 35-7 Comparison of surface roughness produced by common production processes.(Courtesy of American Machinist.)
1135.2 Mechanical Cleaning and Finishing Blast Cleaning
12Finishing Barrel FIGURE 35-8 Schematic of the blow of material in tumblingor barrel finishing. The parts andmedia mass typically account for50 to 60% of capacity.
13Synthetic Media Geometry FIGURE 35-9 Syntheticabrasive media are available in awide variety of sizes and shapes.Through proper selection, themedia can be tailored to theproduct being cleaned
14Vibration Finishing Tub FIGURE Schematic diagram of a vibratory-finishing tub loaded with parts andmedia. The single eccentric shaft drive provides maximum motion at the bottom, which decreasesas one moves upward. The dualshaft design produces moreuniform motion of the tub and reduces processing time
25AnodizingFIGURE The anodizing processhas many steps.
26Nickel Carbide Plating FIGURE (Left) Photomicrograph of nickel carbide plating produced by electroless deposition. Noticethe uniform thickness coating on the irregularly shaped product. (Right) High-magnification cross sectionthrough the coating. (Courtesy of Electro-Coatings Inc.)
35Burr Prevention FIGURE 35-19 Designing extra recesses and grooves into apart may eliminate the need todeburr. (From L.X. Gillespie,American Machinist, November1985.)
36Surface Deformation FIGURE 35-20 Plastic deformation in the surface layerafter cutting. (B. W. Kruszynskiand C. W. Cuttervelt, AdvancedManufacturing Engineering,Vol. 1, 1989.)
37Shot PeeningFIGURE (a) Mechanism for formation of residual compressive stresses in surface by cold plastic deformation (shot peening). (b) Hardness increased in surface due to shot peening.
38Surface Damage as a Function of Rake Angle FIGURE The depthof damage to the surface of amachined part increases withdecreasing rake angle of thecutting tool.
39Surface Stress FIGURE 35-23 (Top) A cantilever-loaded (bent) rotating beam, showing the normal distribution of surface stresses(i.e., tension at the top and compression at the bottom). (Center) The residual stressesinduced by roller burnishing or shot peening. (Bottom) Netstress pattern obtained when loading a surface-treated beam.The reduced magnitude of the tensile stresses contributes toincreased fatigue life.
40Fatigue Life with Surface Finish FIGURE Fatigue life ofrotating beam 2024-T4aluminum specimens with avariety of surface-finishingoperations. Note the enhancedperformance that can beachieved by shot peening androller burnishing.