Tolbert and her colleagues found a way to harden these metals by introducing another element that covalently bonds to these layers, preventing them from slipping without disrupting incompressibility.

• 托伯特和同事发现一种提高这类金属硬度的方法，就是添加可与原子层共价结合的元素，防止原子层滑动，但不影响其抗压缩性。