Flexibility, strength and screening from new alloy

A Sumitomo Electric Industries product story

Edited by the Engineeringtalk editorial team Apr 4, 2002

Sumitomo Electric Industries has developed a highly accurate magnesium alloy wire that is 20% stronger than extruded magnesium alloy bars and can be bent and coiled at room temperature.

Sumitomo Electric Industries has developed a highly accurate magnesium alloy wire that is 20% stronger than extruded magnesium alloy bars and can be bent and coiled at room temperature.

The alloy's flexibility, strength, light weight and other features means it has a wide range of potential applications in electronic devices, leisure and sporting goods, and automotive parts.

For example, the alloy can shield against electromagnetic interference and be easily recycled, making it ideal for use in portable electronic equipment such as cellular phones, notebook PCs, and portable MD players.

SEI also expects demand for the alloy for use as a substitute for resins and aluminium alloy.

Magnesium is the lightest metal among all structural metal materials.

It is one-quarter the density of iron and about two-thirds the density of aluminium; but due to its crystal structure, the workability of magnesium alloy at room temperature is lower than other materials.

Magnesium alloy goods were made only by casting and hot extrusion.

Moreover, the alloy's strength and toughness needed to be further enhanced.

By exploiting its unique technologies of drawing and heat treatment, SEI succeeded in developing a stronger, more flexible magnesium alloy wire.

These features are largely due to the alloy's fine grain size, which is induced by SEI's technologies.

The main features of the alloy are: high dimensional accuracy (tolerance: 1/100mm or less) allowing use in high-precision devices; ductility is equivalent to that of conventional materials (extrusion materials), while tensile strength is 20% percent stronger than conventional materials.

The tensile strength of AZ31 alloy (Al 3%, Zn 1%) is 310MPa and of AZ61 alloy is 370MPa.

Yield stress is enhanced by 50% at the maximum, compared with conventional materials (extrusion materials).

(Yield stress of AZ31 alloy is 260MPa and of AZ61 alloy is 300MPa.) The new alloy can be bent and coiled at room temperature; long wire can be produced; and it can be made in an oval, square and other non-round-shaped cross-sections, with diameters ranging from 0.2 to 7.0 mm.

(This was Engineeringtalk's Top Story on 3 April 2002).