Technique promises stronger, lighter magnesium alloys

Engineers from North Carolina State University have developed a new technique for creating stronger, lighter weight magnesium alloys with potential structural applications in the automobile and aerospace industries.

The team first set out by introducing nano-spaced stacking faults to traditional alloys to isolate any defects in the structure. According to Dr Suveen Mathaudhu, an assistant professor of materials science and engineering at NC State, this increased the overall strength of the material by approximately 200%. "This material is not as strong as steel, but it is so much lighter that its specific strength is actually much higher," he commented. "In theory, you could use twice as much of the magnesium alloy and still be half the weight of steel. "This has real potential for replacing steel or other materials in some applications, particularly in the transportation industry – such as the framework or panels of vehicles." The researchers were able to introduce the nano-spaced stacking faults to the alloy using conventional hot rolling technology. "We selected an alloy of magnesium, gadolinium, yttrium, silver and zirconium because we thought we could introduce the faults to that specific alloy using hot rolling," said Dr Yuntian Zhu, also a professor of materials science and engineering at the university. "And we were proven right." Because the researchers used existing technology, Dr Zhu believes industry could adopt the technique quickly and without investing in new infrastructure.