The hardest alloy is discovered
Titanium is inert enough not to interact with living tissues and not oxidize in the body, but sometimes it lacks strength. On average, titanium prostheses need to be replaced every 10 years due to wear. Therefore, scientists have long been faced with the task of finding another, more durable and at the same time biocompatible material.
Previous experiments with titanium alloys with silver and copper showed good results, but the researchers suggested that if you use a metal in the alloy that is similar in properties to copper or silver, but with a larger atomic mass, the alloy will be stronger. The choice was stopped on gold: it has long been used in prosthetics.
Study leader Professor Emilia Morosan of Rice University in Houston, Texas, said the discovery was made by studying magnets made of titanium and gold. To test the substance for impurities, the laboratory staff needed to obtain metal powder from the samples. In the case of Ti3Au, this failed: the diamond grater could not cope with the alloy. After a series of experiments, it was possible to identify the ideal ratio of metals in the alloy. As a result, the metal was four times stronger than those that are now used in the manufacture of prostheses.
The results of the study are published in the journal Science Advances .