How to control the quality of composites?

The quality of composites is mainly reflected in bonding strength and wall thickness. Therefore, controlling the quality of composites essentially involves controlling these two factors. Bonding strength is influenced by pre-treatment; achieving an Sa2.5 level of pre-treatment can result in higher bonding strength when inserting the plastic tube into the metal tube. Additionally, it is determined by the medium-frequency/ultrasonic-frequency temperature. By controlling the heating temperature between 180°C and 200°C, the plastic tube can reach its optimal physical state, thereby enhancing bonding strength. Wall thickness is jointly determined by the wall thickness of both the plastic tube and the metal tube. Mature metal tube production processes result in wall thickness deviations that do not affect the overall wall thickness of the lined composite tube. Therefore, controlling the wall thickness of the plastic tube becomes a top priority.