磨损
超声磨损主要分为三类 —
- 空化冲蚀发生在材料暴露于空化流体中时。空化气泡的溃灭会产生强烈的冲击波和微射流，进而造成高度局部化的表面应力。气泡反复溃灭使这种载荷不断重复，导致局部表面疲劳失效，随后材料碎块脱落或剥落。（Brennen，第 3.6 节，第 91 页）
- 磨粒磨损发生在坚硬粗糙表面在较软表面上滑动时——例如，变幅杆在玻纤增强塑料上振动时发生的磨蚀。磨粒磨损速率取决于接触材料之间的相对硬度。
- 微动磨损发生在两个接触表面经历小幅值循环运动（振荡切向位移）时。微动磨损是连接处和金属焊接工装表面的一个问题。
Wear
Ultrasonic wear falls into three main categories —
- Cavitation erosion occurs when a material is exposed to a cavitating fluid. The collapsing cavitation bubbles cause intense shock waves and microjets which, in turn, cause highly localized surface stresses. Repetition of this loading due to repeated bubble collapses causes local surface fatigue failure and the subsequent detachment or flaking off of pieces of material. (Brennen, section 3.6, p. 91)
- Abrasion occurs when a hard rough surface slides across a softer surface — for example, when a horn abrades as it vibrates against a glass-filled plastic. The rate of abrasion depends on the relative hardnesses between the contacting materials.
- Fretting occurs when two contacting surfaces experience cyclic motion (oscillatory tangential displacement) of small amplitude. Fretting is a problem at joints and metal welding tooling surfaces.