A method of pre-treating an electrically conductive substrate (12) for bonding a non-metallic material (14) thereon is provided. The method includes: (a) placing the substrate (12) in a laser range of a laser source (16); and (b) irradiating a surface (18) of the substrate (12) with a laser light (24) from the laser source (16), thereby forming a micro-structure (20) on the substrate surface (18). The micro-structure (20) has at least one of: a) an I/Ra ratio of at least 0.2 µm-1, I being the surface index, Ra being the average roughness; or b) an I/Rz ratio of at least 0.03 µm-1, I being the surface index, Rz being the average peak-to-valley distance. An electrically conductive substrate (12), a metal insert (12, 603) for use with a solid insulation component (704, 706, 712, 714), an insulator-conductor assembly (26), and a gas-insulated switchgear station (700) are also provided as well as use of an insulator-conductor assembly (26, 600) in an electrical power system (700).