Hot spinning formability of aluminum alloy tube

Abstract

Spinning is a processing method in which a metal material such as a plate or pipe is pressed against a roller tool while rotating material with a forming die. Hot spinning processing is used for the production of high pressure hydrogen storage container. As an aluminum liner material for a high pressure hydrogen storage container, an Al-Mg-Si alloy is used from the viewpoint of hydrogen embrittlement resistance and strength. However, wrinkles and cracks generated during the formation of the liner material by hot spinning may cause breakage of the container. In this study, hot spinning is performed on Al-Mg-Si (A6063) alloy by changing processing conditions and processing temperature. After that, the effect of processing conditions and processing temperature on surface texture and wall thickness change was investigated. The results are followings, if the number of passes is large, the unevenness of the inner surface is small, but the length of the processed portion increases and the wall thickness decreases. On the other hand, when the temperature is high, the unevenness on the inner surface become large, the length of the worked portion hardly increases, and the wall thickness increases.