Ultrasonic welding method for wood-plastic composite

The invention provides an ultrasonic welding method for a wood-plastic composite, and belongs to the technical field of wood-plastic composite connection methods. The method comprises: 1) preparation of an energy-conducting strip: performing hot press molding on the raw materials comprising 94-98% by weight of polypropylene and 2-6% by weight of maleic anhydride grafted polypropylene to obtain the energy-conducting strip; 2) placing the energy-conducting strip between two wood-plastic composites; 3) heating the contact surface of the two wood-plastic composites by using the energy of ultrasonic waves to generate a partial melt state; 4) increasing pressure through a pneumatic device to fuse the surfaces of the two wood-plastic composites; and 5) processing the welded surface of the wood-plastic composite. By stretching of a universal mechanics tester, a test piece has a breakage at the body but not at the welded joint, thereby it is illustrated that the shear stress borne by the welded surface exceeds the ultimate tension of the body of the wood-plastic composite, and the demand of rapid seamless connection wood-plastic composites is satisfied.