深潜器耐压壳用钛合金保载疲劳服役可靠性研究进展

Research Progress in Dwell Fatigue Service Reliability of Titanium Alloys for Pressure Shell of Deep-Sea Submersible

深海潜水器耐压壳材料的服役可靠性直接关乎深潜器的作业安全,钛合金因其优异的深海环境服役性能成为制造深潜器耐压壳的关键材料。本文从深潜器用钛合金的种类出发,详细介绍了钛合金室温蠕变、低周疲劳及保载疲劳等主要失效形式的最新研究进展,归纳了钛合金保载疲劳的主要影响因素、微观损伤机制及寿命预测模型,以期为新型高强低保载效应的高性能钛合金研发提供参考。最后,提出了目前深潜器用钛合金构件服役可靠性评价亟待解决的若干问题和未来的研究方向。

Service reliability of deep-sea submersible pressure shells is critical for ensuring the safety of the submersibles.To manufacture pressure shells for deep-sea submersibles,titanium alloys have emerged as key materials owing to their exceptional service performances in the deep-sea environment.Herein,use of titanium alloys in deep submersibles is introduced.Then,the latest research on the primary failure modes of titanium alloys,including creep at room temperature,low cycle fatigue,and dwell fatigue,based on the types of titanium alloys used in deep-sea submersibles is reviewed.Additionally,the main factors that affect dwell fatigue,including the micromechanism of dwell fatigue damage and dwell fatigue model,are summarized.This work can serve as a reference for the development of new titanium alloys with high strength and low dwell effect.Finally,specific issues related to the service reliability evaluation of titanium alloy components used in the deep sea are outlined,and future research focuses are presented.