New metals are moldable like plastic

New forms of metal can be turned into complex shapes easily and inexpensively like

plastic but retain the metals' strength and durability, U.S. researchers say.



Materials scientists as Yale University say some recently developed bulk metallic

glasses—alloys with randomly arranged atoms rather than ordinary metals' rigid,

orderly structure—can be blow molded like plastics into complex shapes that can't be

achieved using regular metal but without sacrificing any of the metals' characteristic

strength.



"These alloys look like ordinary metal but can be blow molded just as cheaply and as

easily as plastic," says Yale scientist Jan Schroers, whose team has created a number

of complex shapes including seamless metallic bottles, watch cases, miniature

resonators and biomedical implants, molded in less than a minute and twice as strong

as typical steel, a Yale release reported.



The alloys—made up of different metals, including zirconium, nickel, titanium and

copper—cost about the same as high-end steel, Schroers says, but can be processed as

cheaply as plastic.



The team blow molded the alloys at low temperatures and low pressures, where the bulk

metallic glass softens dramatically and flows as easily as plastic.



To carefully control and maintain the ideal temperature for blow molding, the team

shaped the alloys in a vacuum or in fluid.



"The trick is to avoid friction typically present in other forming techniques,"

Schroers says. "Blow molding completely eliminates friction, allowing us to create any

number of complicated shapes."



In addition, the researchers say, blow molding combines three separate steps in

traditional metal processing—shaping, joining and finishing—into one step, making

previously cumbersome, time- and energy-intensive processing quick and easy.



"This could enable a whole new paradigm for shaping metals," Schroers says.