Bengal scientists have developed the world’s hardest known self-healing material in a laboratory feat that they say could lead to mobile phone screens that repair their own cracks in less than a second.
The researchers from the Indian Institute of Science Education and Research,Calcutta, and the Indian Institute of Technology, Kharagpur, have synthesised an organic crystalline material with a unique internal molecular structure that spontaneously repairs itself when damaged.
The scientists used a needle to trigger mild to severe cracks in a segment of the material and watched as the cracks automatically reversed themselves within a fraction of a second after the needle pressure was withdrawn.
Self-healing materials have been under study worldwide for over three decades and have entered into engineering applications, mainly for wear-resistance in the construction, automotive and aerospace industries.
They have also entered kitchens in the form of self-healing cutting boards.
But almost all known self-healing materials are soft and amorphous — having an internal structure marked by irregularities and defects — and require some external stimulus such as heat, light or a chemical agent to heal themselves.
“Our self-healing material is 10 times harder than others,” said Chilla Malla Reddy, a chemical sciences professor at the IISER who led the research.