JCN Newswire - Sumitomo Electric Develops High-Strength Magnesium Alloy Wire

FOR IMMEDIATE RELEASE

Sumitomo Electric Industries, Ltd
Tokyo Stock Exchange Code (5802)
Tel: 816 6220 4119
e-mail: www@prs.sei.co.jp

Sumitomo Electric Develops High-Strength Magnesium Alloy Wire 

Osaka, April 2, 2002 - (JCN Newswire) - Sumitomo Electric Industries, Ltd. 
(SEI), a leading Japanese manufacturer of fiber optic components and 
electronic materials, is pleased to announce it developed a highly accurate 
magnesium alloy wire that is 20 percent 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 aluminum 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 
aluminum, though, 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: 1/100 mm 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. 
    Tensile strength of AZ31 alloy (Al 3%, Zn 1%) is 310 MPa* and of AZ61 
alloy is 370 MPa.
  - Yield stress* is enhanced by 50% at the maximum, compared with 
conventional materials 
    (extrusion materials). (Yield stress of AZ31 alloy is 260 MPa* and of 
AZ61 alloy 
    is 300 MPa.)
  - Can be bent and coiled at room temperature.
  - Long wire can be produced.
  - Can be made in an oval, square and other non-round-shaped cross 
sections
  - Possible to select a wire with diameters ranging from 0.2 mm to 7.0 mm.

* MPa: Unit of stress. 1 MPa = 1 N/mm2 (1 N per square millimeter)
*Yield stress: The stress at which strain increases rapidly and permanent 
strain occurs with almost no increase in stress.

Picture attached 
High-strength magnesium alloy wire

Physical properties of metals

Properties              Mg      Al      Ti      Fe      Cu
Relative density        1.74    2.70    4.51    7.87    8.93
Specific heat           0.24    0.22    0.13    0.11    0.09
(cal/g degrees Centigrade)
Young's modulus (Gpa)     45      76     114     190    136
Electrical conductivity   39      64     3.1      18    100
(%IACS)
Heat conductivity(W/mk)   167    238      16      73    394

About SEI - Sumitomo Electric Industries Ltd. (SEI), is one of the 
world-leading   manufacturers of optical fiber and cables, components. 
Since its establishment a century ago, the Company has engineered technical 
change by adopting an aggressive research and development strategy. By 
innovatively fostering home-grown technology and successfully diversifying 
its business into exiting fields, SEI has positioned itself as a key player 
in the global information revolution taking place today. SEI confidently 
looks forward to another century of innovation and growth. Net sales for 
the year ended March 31, 2001 were 1,478 billion yen. 

Contact:
Yutaka Saiki
Corporate Communications Department
Sumitomo Electric Industries
saiki-yutaka@sei.co.jp