Green Fluorescent Transparent Ceramic With Low-Scattering Sintering
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current fluorescent transparent ceramics used in high-power LED and display applications have low density, high light scattering, and require complex high-pressure, high-temperature, and high-vacuum processes, limiting their efficiency and cost-effectiveness.
Innovation Solution
A method for preparing green fluorescent transparent ceramics using a stoichiometric ratio of Ca3-x-yCexAySc2-zBzSi3-mCmO12, involving mixing oxides or carbonates, annealing, high-temperature melting, quick cooling, and subsequent low-temperature annealing and sintering in air or vacuum to achieve high density and adjustable transmittance without the need for special experimental conditions.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional high-pressure, high-temperature, and high-vacuum sintering method is used, then fluorescent transparent ceramic can be prepared, but the process is complex and the density is low (≤98%)
Solution Approach 1:
The patent changes the sintering parameters by using a two-stage process: first high-temperature melting (>1600°C) followed by low-temperature sintering (900-1100°C), eliminating the need for high pressure and high vacuum conditions while achieving high density
Solution Approach 2:
The patent performs preliminary high-temperature melting and quick cooling to form transparent glass before sintering, which prepares the material structure in advance to facilitate densification during the subsequent low-temperature sintering process
2Object-affected harmful factors
If conventional sintering method is used, then fluorescent transparent ceramic can be prepared, but light scattering is serious
Solution Approach 1:
The patent uses low-temperature sintering (900-1100°C) instead of conventional high-temperature sintering, which reduces thermal damage and minimizes light scattering while achieving sufficient densification
Solution Approach 2:
The preliminary high-temperature melting and quick cooling creates a homogeneous transparent glass structure that serves as an excellent precursor, reducing the need for extensive sintering and thereby minimizing light scattering
3Reliability
If high-pressure, high-temperature, and high-vacuum conditions are used, then fluorescent transparent ceramic can be prepared, but the cost is substantial
Solution Approach 1:
The patent eliminates high pressure and high vacuum conditions by using atmospheric or low-vacuum sintering at low temperature, dramatically reducing equipment requirements and manufacturing costs while maintaining high product quality
Solution Approach 2:
The patent uses readily available starting materials (oxides, carbonates, or nitrates) and simple processing conditions that can be implemented with conventional equipment, making the process economically viable
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The method results in high-density, high-quantum-efficiency ceramics with adjustable transmittance, suitable for high-power blue LED or LD devices, offering simplified synthesis and reduced costs while maintaining high performance.
Implementation Method 1
fully melting at a high temperature (more than 1,600° C.); quickly cooling to obtain a transparent glass
Implementation Method 2
annealing at a low temperature of 700-950° C. for 1-10 h to remove an internal stress of the glass
Implementation Method 3
performing crystallization and densification sintering in air or vacuum; holding for 5-80 h, to obtain a fluorescent transparent ceramic
Data Source
AI summary
A preparation method and use of a green fluorescent transparent ceramic are disclosed. The preparation method includes: weighing, according to a stoichiometric ratio, elements present in Ca3-x-yCexAySc2-xBzSi3-mCmO12, in forms of oxides, carbonates or nitrates as raw materials; mixing the raw materials, annealing, melting at a high temperature, cooling and annealing at a low temperature; putting the glass into a high-temperature furnace, holding, raising the temperature, and performing crystallization and densification sintering; finally cutting, reducing and surface-polishing, where A is at least one from the group consisting of Lu, Y, Gd, La and Na; B is at least one from the group consisting of Zr, Hf and Mg; C is at least one from the group consisting of Al and P; x, y, z and m satisfy 0.001≤x≤0.06, 0≤y≤0.06, 0≤z≤0.06 and 0≤m≤0.3, respectively.