visible crack的意思|示意

But still left a visible crack around the perimeter of the rectangle.

但这样还是会在矩形的边上留下一点缝隙。

Removing visible surface corrosion before pitting begins (such as during a C-check) helps prevent conditions that can lead to crack initiation.

在出现斑点之前去除可见的表面腐蚀(诸如c -检)有助于预防发生裂纹。

It is proved by the application that as long as the method is rational and the work is studied fully, the goal of prevention of crack visible by naked eyes can be reached.

实践证明，只要施工方法合理，事先进行充分研究工作，完全可以实现不出现肉眼可见裂缝的防裂目标。