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Titanates are currently used in friction materials worldwide. This study investigates the effects of titanates in friction materials with Low Steel (LS) formulations. A kind of titanate compound is examined with a LS formulation. Test pieces both with and without the titanate are examined using small rotors of gray cast iron. The frictional performance tests use a 1/7 scale dynamometer. The surfaces and the cross-sections are closely observed using a Scanning Electron Microscopic analyzer. Results of the testing on samples without the titanate suggest that frictional effectiveness is sensitive to the load value especially in high speed braking conditions. A Metal Pick Up (MPU) phenomenon, which is one of the significant problems of friction materials, also occurs. The millimeter-sized picked-up metals consist of micron-sized wear debris of iron. The crystalline transformation of the steel fibers around the picked up metals is investigated.

It is known that titanates widely use materials for the Non-Asbestos-and-Organic formulation; NAO has excellent performance such as stability in friction level and low wear for disc brake pads. In our previous report[1], we presented that those brake performance depends on the chemical composition, crystal structure and powder properties of titanates from the dynamometer test results. And we introduced the thrust test machine to evaluate friction materials easily[2]. In this study, we have improved the thrust test condition to the repetition of sliding and stopping instead of the continuous sliding. In this interval method, we have controlled the temperature of the friction surface, and have been able to observe a phenomenon of wear that occurs under high temperature in our laboratory. Then we clarified the correlation between powder characteristics and brake performances.