Recently, the dissolvable magnesium alloys in the field of unconventional oil and gas have attracted considerable attention. However, for these alloys to be applied in oil and gas wells above 200 °C, they need to be made more resistant to high temperatures. In this work, a high-temperature-resistant Bi-xSn (x=9, 12, 15, 18 wt%) coating was prepared by chemical deposition and hot-dipping plating on the dissolvable magnesium alloy. The microstructure, mechanical properties, and dissolution properties of the coating were evaluated. The results demonstrate that Bi-xSn exhibits superior comprehensive mechanical properties. The mechanical interlocking of the substrate with the chemical deposition layer and the hindering effect of the coating on the migration of the substrate grain boundaries ensure the high-temperature mechanical properties of the material. Electrochemical measurements indicated that the corrosion resistance of the coatings decreased and the corrosion rate increased with increasing Sn content. The results of the high-temperature dissolution experiments indicate that the mass change of the Bi-9Sn component is minimal after the 220 °C dissolution experiment, with a dissolution rate of approximately 2.04 mg·cm−2·h−1. The coating has been demonstrated to exhibit superior stability at elevated temperatures, offering a potential solution to the challenges of poor mechanical properties and excessive dissolution of soluble fracking tools in high-temperature downhole environments. Which provides a novel concept for the development of downhole tool materials for high-temperature (220 °C) oil and gas wells.

中文翻译：

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可溶性镁合金耐高温（220℃）Bi-xSn涂层的制备及性能研究


近年来，可溶性镁合金在非常规油气领域的应用引起了人们的广泛关注。然而，为了使这些合金应用于200℃以上的油气井，需要使其更耐高温。本工作通过化学沉积和热浸镀在可溶性镁合金上制备了耐高温Bi-xSn（x=9、12、15、18 wt%）涂层。对涂层的微观结构、力学性能和溶解性能进行了评价。结果表明，Bi-xSn 表现出优异的综合机械性能。基体与化学沉积层的机械互锁以及涂层对基体晶界迁移的阻碍作用保证了材料的高温力学性能。电化学测试表明，随着Sn含量的增加，镀层的耐腐蚀性能下降，腐蚀速率增加。高温溶解实验结果表明，220 ℃溶解实验后，Bi-9Sn组分的质量变化最小，溶解速率约为2.04 mg·cm−2·h−1。该涂层已被证明在高温下表现出优异的稳定性，为解决高温井下环境中可溶性压裂工具机械性能差和过度溶解的挑战提供了潜在的解决方案。这为高温（220℃）油气井井下工具材料的开发提供了新颖的理念。