Cao Haohua, Dong Fang, Zhang Qiang, Wu Hao
State Key Laboratory of Precision Manufacturing for Extreme Service Performance, Central South University, Changsha 410083, China; Light Alloy Research Institute, Central South University, Changsha 410083, China.
State Key Laboratory of Precision Manufacturing for Extreme Service Performance, Central South University, Changsha 410083, China; Light Alloy Research Institute, Central South University, Changsha 410083, China.
Ultrason Sonochem. 2025 Feb;113:107224. doi: 10.1016/j.ultsonch.2025.107224. Epub 2025 Jan 7.
The chemical corrosion of the TC4 radiation rod surface (TRRS) during the ultrasonic casting process has the potential to significantly impair the smooth conduction of ultrasonic waves. However, in the later stages of corrosion, a self-protected structure (TSPS) emerges under the ultrasonic cavitation effect, which serves to impede the chemical corrosion of the TRRS and markedly reduce the rate of mass loss of the radiation rod. This ensures the smooth ultrasonic conduction of the radiation rod during operation. In this paper, an analysis of the microstructure of TSPS was conducted. The surface energy ratio at different crystal planes in TC4 and the self-diffusion coefficient for two phases of Ti in TC4 were calculated. The results indicated that TSPS is characterized by α-Ti grain basal planes concentrated parallel to the TRRS, higher α phase content, and fewer crystal defects. TSPS not only inhibits Ti dissolution and delays the onset of chemical corrosion, but also reduces the chemical corrosion rate.
超声铸造过程中TC4辐射棒表面（TRRS）的化学腐蚀有可能显著损害超声波的顺利传导。然而，在腐蚀后期，在超声空化作用下会出现一种自保护结构（TSPS），它有助于阻碍TRRS的化学腐蚀，并显著降低辐射棒的质量损失率。这确保了辐射棒在运行过程中超声波的顺利传导。本文对TSPS的微观结构进行了分析。计算了TC4中不同晶面的表面能比以及TC4中Ti两相的自扩散系数。结果表明，TSPS的特征是α-Ti晶粒基面平行于TRRS集中，α相含量较高，晶体缺陷较少。TSPS不仅抑制Ti溶解并延迟化学腐蚀的开始，还降低了化学腐蚀速率。
