The company has an ironclad policy against revealing secrets to competitors.

公司有个铁定的政策 禁止向竞争对手透露秘密

These ironclad details are irrefutable proof in black and white.

白纸黑字，铁证如山。

That ironclad image is now tarnished.

如今，这种稳如磐石的形象开始动摇。

But the support isn't always ironclad.

但这种支持并非一成不变。

A series of ironclad facts put him to silence.

一系列铁的事实驳得他哑口无言。

Actually, these selection rules are not ironclad.

实际上，这些选择规则并不是严格的。