Enhancing materials such as steel can be difficult because you end up creating new weaknesses simultaneously. Put simply, the whole feat becomes a balancing act between different sets of properties. A team of engineers has managed to create a new sort of super steel that successfully managed to break free from this paradox. It can remain strong while still being capable of resisting fractures.
Steel has three primary properties that need to be balanced – ductility, strength, and toughness. The last two might sound like the same thing but they are completely different. Strength is defined as the load that a material can take before it fails and is measured in Pascals whereas toughness implies how much energy is required to fracture a material.
Ductility, on the other hand, is how easily you can extend or elongate a material into various shapes. A team of researchers at the University of Hong Kong and Lawrence Berkeley National Labs (LBNL) claims to have created a new type of steel – super steel – that offers top-notch performance in all three properties. This super steel has a yield strength resistance against deformation of almost 2 GigaPascals, fracture toughness of 102 MPa- m½ and uniform elongation of 19%. The team said that this makes the super steel tougher and stronger than the Grade 300 maraging steel that is employed in aerospace engineering. Furthermore, this new kind of steel costs 20% of the price to create Grade 300 maraging steel.
The lead author of the study – Huang Mingxin said, ‘We have made a big step closer to industrializing the novel super steel. It demonstrates a great potential to be used in various applications including superior bulletproof vests, bridge cables, lightweight automobile, and military vehicles, aerospace, and high strength bolts and nuts in the construction industry.’
The research of the team has been published in Journal Science.