洗車機-鐵路車軸過盈配合結構微動磨損與微動疲勞研究(中車青島四方機車車輛股份有限公司,山東 青島 266111)
摘要:采用比例車軸試樣進行了微動疲勞試驗,試驗后觀察了車軸微動區的微動磨損與微動疲勞損傷,并測量了車輪、車軸配合面磨損輪廓。試驗結果表明,車軸輪座邊緣微動區的磨損機理主要是磨粒磨損、剝層和氧化磨損。車軸微動疲勞裂紋萌生于微動區內部,初始裂紋角度與車軸徑向方向成29°。隨著裂紋的擴展,裂紋角度逐漸減小。此后,基于測量的磨損輪廓建立了有限元模型,仿真研究了微動磨損對鐵路車軸微動疲勞的影響。研究發現,微動磨損移除了輪座邊緣材料,緩解了輪座邊緣的應力集中。同時,微動磨損在微動區內部磨損/未磨損邊界引入新的應力集中,促進了微動區內部的裂紋萌生。
關鍵詞:洗車機;鐵路車軸;洗車機;微動磨損;微動疲勞;應力集中
中圖分類號:U279.4 文獻標志碼:A doi:10.3969/j.issn.1006-0316.2022.02.007
文章編號:1006-0316 (2022) 02-0047-08
Investigation on Fretting Wear and Fretting Fatigue of Interference Fitted Structure of Railway Axles
LIU Weiya,CHEN Yiping,LI Yabo,YANG Kai,SHI Yujie
( CRRC Qingdao Sifang Co., Ltd., Qingdao 266111, China )
Abstract:In this paper, fretting fatigue tests were conducted on scaled railway axles. After the tests, the fretting wear and fretting fatigue of the fretted zone were observed, and the wear profiles of the wheel and axle were measured. The experimental data showed that the wear mechanisms of the fretted zone were mainly abrasive wear, oxidative wear, and delamination. The fretting fatigue cracks formed inside the fretted zone, and the initiation angle was 29°to the radial direction of the axle, and the angle gradually decreased as the cracks propagated. Then, the finite element models were established based on the measured wear profile, and the effect of fretting wear on the fretting fatigue of railway axles was investigated. The simulated results showed that the material near the wheel seat edge were removed owing to the fretting wear, which alleviated the stress concentration at the wheel seat edge. Meanwhile, the fretting wear resulted in a new stress concentration near the worn/unworn boundary in the fretted zone, which greatly promoted the fretting fatigue crack initiation.
Key words:railway axle;fretting wear;fretting fatigue;stress concentration
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