Research On Separation Of Laminated Glass By Multi-focus Laser

Laminated glass materials are widely applied in the field of construction,automotive,aerospace and other fields due to their excellent properties.However,for the processing of laminated glass at this stage,the cutting method using mechanical force separation after sawing or diamond scribing still remains.Not only the cutting efficiency is low,but also the quality of the cutting seam is poor,and subsequent edge grinding and other processing processes are required,which cannot completely meet the requirements of high-quality and high-efficiency application.The laser crack control method has the advantages of straight slits,no debris,and no micro-cracks,and does not require further grinding and cleaning.However,since the processing of a single laser focused spot is limited by the thickness of material,it cannot be used for laminated glass lasers with a multilayer structure.In this dissertation,an innovative method of multi-focus laser cutting and separating for laminated glass is proposed.The method is based on the laser thermal cracking control method and the melting/gasification principle,and uses a plurality of ring-focusing lenses to form a multifocal lens,forming a plurality of laser focal points along the thickness of the transmission material,so that each layer of the transmission material has different laser energy.At the same time cutting and separation the transmission material by different mechanisms,such as brittle transmission materials(glass and crystals)can be cut and separated by thermal cracking control methods,while non-brittle transmission materials(PVB and other polymer materials)are melted to achieve high quality and one-off integral cutting and separation of laminated glass.Through the combination of theoretical calculation and ZEMAX optical design software simulation,an optical path system capable of forming three focal points was designed and the accuracy of the system was verified by comparing theoretical calculations,software simulations and focal position and energy distribution in an actual air medium.The multi-focus laser processing system was used to cut and separate 5+5 and 3+3 laminated glass.Experiments show that by adjusting parameters such as laser power,scanning speed,and focus position,it is possible to obtain a high-quality cross-section with smooth,no subsurface damage and small roughness,effectively solving the problem of single laser focus thermal cracking control method can not be used to separate laminated glass.In addition,the method successfully cuts and separates brittle transmission materials such as single-layer glass with a thickness of 10-20 mm,ultra-white glass,which proves the feasibility of multi-focus laser cutting and separation of thick and brittle transmission materials.It has great application prospects.