Purdue Researchers Develop New High-Strength Aluminium Alloy

Purdue Researchers Develop New High-Strength Aluminium Alloy
In this photo, Qiang Li makes a deposition program on the operational computer, and Yifan Zhang loads samples into a sputtering chamber to prepare high-strength Al alloy coatings. Source: Purdue University

Researchers at Indiana’s Purdue University say they have developed a new high-strength aluminium alloy coating for use in the aerospace and automotive industries.

The research team, headed up by by professor Xinghang Zhang of the university’s School of Materials Engineering, says the work is an extension of a breakthrough announced earlier this year regarding the discovery of a particular stacking fault and its translation to greater strength in aluminium.

“We have created a very durable and lightweight aluminum alloy that is just as strong as, and possibly stronger than, stainless steel. Our aluminum alloy is lightweight and provides flexibility that stainless steel does not in many applications.”

Per the researchers, a coating made from the alloy, which uses stacking faults that distort the metal’s crystal structure to form nanotwins, can form coatings that are highly corrosion- and wear-resistant. Such a quality is of obvious use to several applications within both the automotive and aerospace sectors.

Purdue doctoral student and research team member Qiang Li elaborated upon the stacking fault and its attributes.

“The 9R type of stacking fault is usually rare in aluminum. We introduce both twin boundaries and 9R phase within nanograins to the lightweight Al alloys that are both strong and highly deformable under stresses. Besides coating applications, we are also looking into scale-up potentials of bulk high-strength Al alloys.”

In addition to the alloy described above, the team has also developed a different alloy that involves the introduction of iron or titanium into the raw aluminium. Per the team, the resultant aluminium-iron alloy is among the strongest aluminium alloys ever developed, rivaling its strength to that of steel.

Both findings have been published in the journals in Advanced Materials and Scripta Materialia, and the process behind the new alloys is currently secured by a patent held by the university.