The present work unveils the features of heat dissipation and acoustic emission accompanying the fatigue crack growth in a titanium alloy (Ti-0.8Al-0.8Mn and Ti Grade 2) using the compact tension and Charpy V-notch specimens. The quantitative measurements of the heat dissipation rate were carried out by an original heat flux sensor. The obtained results reveal that there exist two appreciably different stages of the crack propagation within the stable Paris regime. Relationships between the crack growth rate and the heat dissipation rate are proposed for both stages. The application of the non-supervised clustering algorithm to the continuously recorded acoustic emission signal helped to identify two dominant mechanisms of stress relaxation that occur ahead of the crack tip—mechanical twinning and crack opening. The correlation between the acoustic emission energy and heat dissipation was found to be a harbinger of the approaching transition from stable to unstable crack growth.

本工作使用紧凑的张力和夏比V型缺口试样揭示了钛合金（Ti-0.8Al-0.8Mn和Ti 2级）中随着疲劳裂纹扩展而产生的散热和声发射的特征。散热率的定量测量是通过原始的热通量传感器进行的。所得结果表明，在稳定的巴黎体系内，存在两个明显不同的裂纹扩展阶段。提出了两个阶段的裂纹扩展速率和散热速率之间的关系。将非监督聚类算法应用于连续记录的声发射信号有助于确定出现在裂纹尖端之前的两种主要应力松弛机制-机械孪生和裂纹张开。