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define its cross-sectional shape) or flattened by roll-flattening round wire into a rectangular shape with rounded corners. Drawing and cold finishing result in much tighter tolerances on thickness than rolling, which in turn produces more precise dimensions than extruding (ASTM B221, Extruded Bars, Rods, Wire, Shapes, and Tubes).

The round products (wire and rod), when produced for subsequent forming into fasteners such as rivets or bolts, are called rivet and cold-heading wire and rod (ASTM B316). Rivet and cold-heading wire and rod is produced in the alloys and with the strengths shown in Table 9.24; these alloys have good machinability for threading. Rivet and cold heading wire and rod, and the fasteners produced from it, shall upon proper heat treatment be capable of developing the properties presented in Table 9.24.

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