Abstract Subsurface crack networks surrounded by microstructural alterations, named as “White Etching Cracks” (WEC), lead to wind turbine gearbox bearing (WTGB) premature failures. This phenomenon has been studied for decades without yet reaching a sturdy and justified cause of its occurrence. This paper reviews the most recent literature regarding WEC discussing steel microstructural alterations, WEC initiation modes, main WEC drivers, experimental procedures, as well as the influence of coatings and heat treatments on the occurrence of this phenomenon. A broad insight of the effect of each driver in WEC formation is presented and an undisclosed hypothesis related to WEC initiation is suggested. From this work it may be concluded that in the majority of the tests where WEC has been generated, three drivers usually appear and act synergistically: non-metallic inclusions, sliding and hydrogen.

中文翻译：

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风力涡轮机齿轮箱轴承“白色蚀刻裂纹”故障的广泛回顾：主要因素和实验研究

摘要 被微观结构改变包围的地下裂纹网络，称为“白色蚀刻裂纹”（WEC），导致风力涡轮机齿轮箱轴承（WTGB）过早失效。这种现象已经研究了几十年，但尚未得出其发生的可靠和合理的原因。本文回顾了有关 WEC 的最新文献，讨论了钢的显微组织变化、WEC 引发模式、主要 WEC 驱动因素、实验程序，以及涂层和热处理对这种现象发生的影响。提出了对每个驱动程序在 WEC 形成中的影响的广泛见解，并提出了与 WEC 启动相关的未公开假设。从这项工作中可以得出结论，在生成 WEC 的大多数测试中，通常会出现三个驱动因素并协同作用：