In recent years, using aluminum materials in place of steel or iron is becoming more common. The specific weight of aluminum is only 35% of steel (7.9). Therefore, 65% weight reduction is possible.

=Weight reduction by adopting aluminum alloys=

·While being more lightweight compared to steel, aluminum alloys are susceptible to deformation since the Young's modulus is approximately one third of the steel's. Thus, they are not the good choice of structural members requiring accuracy and strength.

·Because aluminum alloys are suited to continuously manufacturing products in complex shape by extrusion, they are chosen as the base materials of aluminum frames for covers and sashes. In this case, adopt the cross-section shape with the greater secondary factor for the frames to make the structural member lightweight and strong (see [Fig.1]).

·Aluminum is also adopted as structural frames of a worktable for prototype production line or jigs for small-lot production such as for trial or research purposes (see [Fig.2]).

·Aluminum alloys must go through welding process if you use them as large-sized structural members. Friction Stir Welding Method (patented in the U.K.) is a frontier technology of welding work. This method is adopted for manufacturing bullet train cars and high-speed vessels (see [Fig.3]).

·In the production facility of an automation device, aluminum materials are used for precision surface plates assembled to lightweight and high-precision tables. In this case, apply hard anodic oxide coating to improve abrasion resistance on the surface and increase the surface hardness before use.