Abstract
The global warming phenomenon by CO_2 emitted from cars is mentioned as one of the most serious matters in global environment problems. It is thought that the improvement in rate of fuel consumption is expected by development of the lightweight transport machine made of many aluminum parts, and it leads to the improvement of an environmental problem. Bending of extruded aluminum pipes is used in many cases as secondary forming. There is press bending processing of extruded aluminum pipes. It is the final purpose of this study to increase processing limit on bending.
