Internal Friction in Rail Waist of BNb and BNbRE Steels
摘要
The internal frictions of the specimens in the waist centre of the commercial BNb and BNbRE rails, which were left in air for two years, were measured. It is found that there is an obvious Snoek-Ke-Kster (SKK) peak in both steels, and still exists a measurable deformation-enhanced Snoek peak(DESP) in the specimens of the BNbRE steel. The internal frictions in the deformed specimens of the both steel rails were also measured. Unlike the case of the tread specimens showing a decrease of SKK damping due to deformation, the SKK damping of the rail waist specimens increases after deformation; and the specimens containing rare earth(RE) show more noticeable damping increase than those without RE. The results of the internal friction measured during ascending and descending temperature under 700 ℃ show that there is a high temperature damping which can be completely disappeared during descending temperature for both steels.