Preparation And Performance Of Fluorescent Glass Ceramic Phosphors Based On 3D Printing

Solid-state lighting light source has the characteristics of energy conservation,environmental protection and long service life,and is gradually replacing traditional light sources such as fluorescent lamps and incandescent lamps in lighting,display and other fields.Compared with traditional organic resin encapsulated fluorescent powder combined with blue LED to obtain white light source,the blue LED system based on fluorescent glass ceramics（GCs）has the characteristics of high efficiency,good thermal conductivity,and strong light output brightness.However,due to the high melting point,brittleness,and high hardness of glass matrix,the preparation and processing of fluorescent glass ceramics face great difficulties.Laser and 3D printing technology have potential advantages in the processing and manufacturing of fluorescent glass ceramics due to their high efficiency and economy,which can meet their needs in ultra-thin layers,high precision,complex structures,and personalized devices.This thesis addresses the difficulties in the processing of large-sized thin films and the preparation of complex irregular structures for fluorescent glass ceramics.YAG:Ce³⁺-GCs thin films with good stability and high efficiency,as well as YAG:Ce³⁺-GCs with high complexity network structure,were prepared using laser sintering method and photocuring 3D printing technology,respectively.The results showed that the prepared YAG:Ce3+-GCs thin film achieved high lumen output of white light through a combination system with blue LED.The main research content of this thesis is as follows:（1）In response to the high difficulty and long cycle of preparing fluorescent glass ceramic thin sheets,a selective laser sintering method was used to study the preparation and performance of fluorescent glass ceramic thin sheets.A series of YAG:Ce³⁺-GCs fluorescent glass ceramic thin films with different processing conditions were obtained through orthogonal design optimization of various parameters of CO₂ laser,including power,scanning speed,preheating temperature,and scanning interval.By combining with blue light LED chips,the effects of thickness of fluorescent glass ceramic sheets and different heat treatment conditions on the color and stability of white light LED luminescence were studied.The results show that the prepared fluorescent glass ceramic thin sheets have high quantum efficiency（about 83.4%）,good time stability（maintaining 99.5%luminous flux for 110 hours）,and extremely fast preparation speed,indicating that the selective laser sintering method has the potential to be applied in the preparation of fluorescent glass ceramic as a rapid manufacturing technology.（2）In order to meet the current demand for highly complex,high-precision and personalized optical devices,a highly complex YAG:Ce³⁺-GCs fluorescent glass ceramic body with reticular structure was prepared using Digital Light Processing（DLP）technology.The effects of different sintering temperatures and times on the morphology and optical properties of the prepared samples were studied.The results showed that the prepared YAG:Ce³⁺-GCs fluorescent glass ceramic body exhibited high internal quantum efficiency（77.6%）,high density（2.718g/cm³）,and high densification（93.6%）.This method provides a way for the future manufacturing of highly complex,high-precision,and personalized luminescent material optical devices.