High Adhesive Force between Laminated Sheets of Titanium and Polyurethane Improved by Homogeneous Low Energy Electron Beam Irradiation Prior to Hot-Press

Abstract

2-layer copper/polyurethane (Cu/PU) laminated sheets were prepared by a new adhesion method, a double-step treatment consisting of applying low dose (1⁄40.43MGy) homogeneous low energy electron beam irradiation (HLEBI) prior to hot-press under 5MPa and 413K. Although the weak hot-press adhesion of the Cu/PU was observed without HLEBI, the new adhesion raised the bonding forces as evidenced by the mean adhesive forces of peeling resistance (Fp). Based on the 3-parameter Weibull equation, the lowest Fp value at peeling probability (Pp) of zero (Fs) could be estimated. An increasing trend in Fs occurred by the double-step treatment applying HLEBI up to 0.13MGy reaching a maximum at 27.1Nm11, improving the safety level without radiation damage. When HLEBI cut the chemical bonds in PU polymer and generated terminated atoms with dangling bonds, they probably induced the chemical bonding and intermolecular coulomb attractive forces. Therefore, increasing adhesion force between the laminated sheets could be explained. [doi:10.2320/matertrans.MBW201312]