As the interface follows the solidification front of the shell metal, the areas of soft core metal showing at the barrel surface, will be patchy and not continuous.

由于结合层往往是沿着外层金属的凝固线所形成的，因此在辊身表面所呈现的此类缺陷是不连续，不规则的。

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In the next phase, a fatigue, cat's tongue like fracture band propagates progressively in a circumferential direction running more or less parallel to the barrel surface.

在下一个阶段，疲劳会逐渐向圆周方向漫延，呈现出平行于辊身表面的猫舌状断裂带。

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One effective way is preferred pump barrel and plunger of materials and surface treatment processes.

其中一个有效的方法就是优选泵筒和柱塞的材料和表面处理工艺。

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The typical barrel of a high-power rifle has exterior grooves, called flutes, to reduce weight and create more surface area to enable the barrel to cool faster.

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Beneath my hand, the barrel of the weapon was oily and slick, and I caressed its surface for long minutes as if touch in itself were reassurance and consolation.

NEWYORKER: Rat Beach