轻松英语阅读：世界上最坚硬的材料

It’s the material at the tip of a pencil and it has the potential to revolutionize our lives. A study from Columbia University has shown that graphene is the strongest material in the world. In fact , it is much tougher than diamonds and 300 times stronger than steel.

Until now, it was thought that graphene would only be strong at the atomic level and that it would weaken if it were not in one piece. But this study showed that it may be able to keep its exceptional strength at much larger sizes. The new research also shows that if pieces are put together, they remained 90 percent as strong as the original. This strength will be invaluable for ultra strong composite materials and flexible electronic devices like a roll up television screen or smartphone.