Watchmakers will soon have a new exotic case metal to boast about when Ti3Au makes it to market. Developed by scientists at Rice University and Texas A&M University as a byproduct of research into magnets, Ti3Au is a combination of titanium and gold with a crystalline structure. The nature of the metal gives it several useful properties, including being four times as hard as pure titanium. Ti3Au has a maximum hardness of 800 HV when the proportion of gold in the metal is 25 per cent, compared to about 200 HV for stainless steel. Lange’s honey gold alloy, for instance, has a Vickers hardness of 300 HV.

The new alloy also has a low coefficient of friction – tests show it wears down 70 per cent less than titanium – meaning it lasts longer (image above shows results of wear tests on the metal). Ti3Au also adheres well with ceramic and is biocompatible, meaning it can be put inside the human body with no ill effects. In fact, Ti3Au is the hardest known biocompatible alloy.

The obvious utility for Ti3Au is medical implants, but with such alluring properties (Ti3Au can probably fill two whole pages of a press release), the metal will probably reach the outside of the wrist one day.

Source: Science Advances