Due to the inevitable flow-induced vibration and turbulent excitation in steam generator (SG), it is impossible to avoid fretting wear or impact between steam generator tubes (SGTs) and anti-vibration bars (AVBs). Therefore, the approach of this work was to simulate the real fretting problems between SGTs and AVBs. Thus, the impact-sliding fretting wear tests of 690TT alloy/405 stainless steel (405 SS) were investigated under various contact times in tube/plate configuration and tube/cylinder configuration in air at room temperature, respectively. The results indicated that the influences of contact geometry and contact time on the peak radial force (Frp) were insignificant, while the value of peak tangential force (Ftp) was seen to increase with increasing contact time and was associated with the contribution of sliding wear to impact-sliding process. Meanwhile, the degree of wear damage increased with the increase of contact time, either line contact or point contact. The damage area of wear scar in tube/plate configuration was evidently larger than that of tube/cylinder configuration. Instead, the maximum wear depth of tube/cylinder configuration was larger than that of tube/plate configuration. Along the sliding direction, the “U" shape profiles were usually detected whether tube/plate configuration or tube/cylinder configuration. In general, both contact geometry and contact time had a direct influence on the behavior of wear debris, i.e., movement and oxidation.
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