In the radial tire industry, stainless steel wires are used extensively. These wires are coated with brass (Cu, Zn alloys) and can contain two separate phases of brass, alpha and beta. Ideally, these wire coatings should be completely or predominantly alpha-phase brass. If the beta phase concentration becomes too large, it affects the wire strength while pulling through the dyes and causes the wire to snap. The beta phase also decreases the adherence of the wires to rubber, resulting in a weakening in the overall tire strength.
Quantification of the alpha to beta brass ratios can easily be accomplished with the MiniFlex diffractometer as part of an on-line quality control program.
Figure 1: The various gauges of brass coated steel wire for diffraction analysis
Figure 2: Diffraction pattern of a 1.58 gauge wire. Red lines correspond to the alpha brass phase. Blue lines correspond to the beta brass phase.