Tool Design of Heating Plastic Connection for Unequal Diameter Aluminum Thin-Walled Tubes

Abstract:

Aluminum thin-walled tube can be cracked during axial compression connection， which can result in connection failure. To improve the compressional plastic formability of aluminum alloy， a heating plastic connection tool for unequal diameter thin-walled tubes was designed in the paper. The thermal stress and heat transfer of the tool in the process of heating plastic connection were numerically simulated by finite element software. The cooling system structural parameters were analyzed by using the orthogonal test method. The tool and the trial unequal diameter aluminum joint were manufactured. The results show that the maximum stress of the tool at 20 ℃ and 600 ℃ are lower than the yielding strength of the material at the corresponding temperature， which meets the requirements of heating plastic connection process for steel and aluminum. The cooling system designed can effectively slow down the heat transfer from the tool to the tensile machine. The joint of φ44 and φ30 is successfully connected by the tool at 300 ℃， which verifies the rationality of the tool design and the feasibility of the connection process， provideing guidance for subsequent engineering application.

Key words:plastic connection;thin-walled tube;axial instability;tool design