不同温度下690合金传热管与抗振条的微动磨损特性

Fretting wear behavior of alloy 690 heat transfer tubes against anti-vibration strip at different temperatures

在卧式高温微动磨损试验机(PLINT TE77)上,采取线接触方式,研究690合金传热管/405不锈钢抗振条在干态不同温度下的切向微动磨损特性。在试验参数为法向载荷40 N、位移幅值100μ、频率5 Hz和循环次数1次的条件下,分别在25、90、200和285℃这4种不同温度下进行切向微动磨损试验。结果表明:微动工况均处于滑移区,90℃时稳态摩擦因数最高;当温度升高到200和285℃时,摩擦因数经过下降期后出现一个更加明显的下降阶段,这与界面的高温氧化有关。磨损机制是磨粒磨损、氧化磨损和剥层,磨痕表面在低温(25和90℃时的氧化程度比高温(200和285℃时的严重。90℃时的磨损量比其他温度时的都高,这可能与界面水蒸气蒸发和表面摩擦氧化有关。

Tangential fretting wear characteristics of alloy 690 tubes against 405 stainless steel plates were studied on a fretting wear tester (PLINT TE77) under the dry condition at different temperatures by linear contact. At the test parameters, such as normal load of 40 N, displacement amplitude of 100μm, frequency of 5 Hz and cycle number of 1× 10 5, the fretting wear test were carried out at 25, 90, 200 and 285℃. The results show that, the fretting condition are all running in gross slip regime. The friction coefficient at 90℃reaches the highest steady state value, and it occurs a more obvious decrease stage after a period of decline while the temperature increases to 200 and 285℃, which is related with the high-temperature oxidation at the interface. The wear mechanisms are complex with abrasive wear, oxidation wear and delamination. The oxidation of the worn surface at low temperatures (25 and 90℃) is more serious than that at high temperatures (200 and 285 ℃). The wear volume at 90 ℃ is higher than that at the other temperatures, this may be related with the water vapor at the interface and the oxide film at the surface.