Experimental Study on a New Test Apparatus for the Surface Damages Combined with Slurry Wear and Cavitation Erosion

1.将超声振动空化装置与浆体射流装置相结合，构建了一套新的试验装置，用于研究浆体磨损和空化侵蚀的复合损伤。实验结果表明：(1)当空化和泥浆侵蚀共同作用时，由于固体颗粒相继脱离表面，损伤损失量与时间成正比增加，没有潜伏期，与各损伤损失量的简单求和不一致。在低喷流速度下，固体颗粒减少了空化侵蚀。当射流速度较高时，空化气泡从表面流出，固体颗粒消除塑性变形，产生冲蚀碎屑，从而减小空化侵蚀。(2)含固体颗粒的水中空化侵蚀加剧。磨料、石英砂等角状颗粒的损伤增加程度大于玻璃微珠。随着颗粒尺寸的增大，损伤在某一给定值出现最大值，然后逐渐减小。建立了含空化气泡的浆液射流作用于静止试件的试验方法。复合损伤大于泥浆磨损。建立了一套空气冲击冲蚀试验装置，研究了固体颗粒流冲击作用下的磨损特性。在室温和高温条件下，固体颗粒对材料的冲击磨损可以从材料和颗粒的冲击条件以及材料和颗粒的性质来估算，从这些结果可以看出，本研究开发的试验台对于研究泥浆磨损以及泥浆磨损和空蚀联合破坏是非常有用的。

1. A new test apparatus was constructed by combining an ultrasonic vibratory cavitation device and a slurry jet device in order to study combined damages with slurry wear and cavitation erosion. Experimental results were obtained as follows.(1)When cavitation and slurry erosions are combined, the damage loss increases in proportion to time without an incubation period because solid particles remove the surface successively and does not coincide with simple summation of each damage loss. Under low jet flow velocity, cavitation erosion is reduced by solid particles. When jet flow velocity is high, cavitation bubbles flow out from the surface and the solid particles remove the plastic deformations in which produce the erosion debris, thus the cavitation erosion is diminished.(2)Cavitation erosion increases in water containing solid particles. The degree of the increase of damage is larger for angular particles such as abrasives and silica sands than glass beads. With increasing particle size, the damage shows a maximum at a given value and decreases.2. The test method which slurry jet containing cavitation bubbles acts on the stationary specimen was developed. The combined damage is larger than slurry wear.3. An air-blast erosion test apparatus was constructed in order to investigate the characteristics of wear caused by a stream of impinging solid particles. The wear of materials by impacts of solid particles at room and high temperatures could be estimated from the impinging conditions and the properties of materials and particles.From these results, it is found that the test apparatuses developed in this study are very useful to investigate the slurry wear and the damages combined with slurry wear and cavitation erosion.