结果表明荧光显示部位存在明显的显微疏松，榫头处有清晰的磨削痕迹，局部有微裂纹。
The results show that there was obvious microporosity at the positions indicated by fluorescence, and clear grinding traces and some local microcracks were found at the dovetails.
钎焊焊缝的枝晶间显微疏松导致的应力集中与微裂纹效应以及近焊缝区母材晶粒长大是导管早期疲劳开裂的主要原因。
The results show that the crack initiates at the outer surface of the weld comer and propagates into the steel base material with a high cycle fatigue mode.
在显微镜之下，原本看起来很干净的表面其实像砖墙一样凹凸不平，如果这堵墙看起来破烂不堪或疏松易碎，就说明珍珠层没有用。
Under the microscope, the stuff they're after looks like a clean, structurally sound brick wall. If the wall looks ratty or crumbly, it's no good.
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