TECHNOLOGY FOR PRODUCING COMPOSITE GLASS-CRYSTAL FACING MATERIALS BASED ON MIXED CULLET
At a Glance
Section titled âAt a Glanceâ| Metadata | Details |
|---|---|
| Publication Date | 2020-02-20 |
| Journal | Bulletin of Belgorod State Technological University named after V G Shukhov |
| Authors | N. I. Bondarenko, Đ. Đ. ĐŃŃĐșĐ°, Vasiliy Bessmertnyy, S A Chuev, I. A. Izotova |
| Institutions | National Technical University âKharkiv Polytechnic Instituteâ, Belgorod State Technological University |
| Analysis | Full AI Review Included |
Executive Summary
Section titled âExecutive SummaryâThis technical analysis reviews an energy-saving technology for producing high-strength composite glass-crystal (glass-ceramic) facing materials from recycled cullet and porcelain waste. The findings demonstrate significant advancements in sustainable material science, directly linking to 6CCVDâs expertise in high-performance diamond materials for advanced processing and characterization.
- Core Achievement: Development of a composite glass-ceramic material achieving a high compressive strength of up to 79 MPa.
- Energy Efficiency: The technology successfully reduced the optimal sintering temperature from 750 °C to 725 °C by incorporating liquid sodium glass (5 wt. %) and fine porcelain powder (10 wt. %).
- Material Composition: Optimal material relies on a specific fractional composition of mixed cullet (35% 0.63-0.80 mm, 35% 0.80-1.25 mm, 30% 1.25-3.15 mm).
- Strengthening Mechanism: Fine porcelain cullet acts as a strengthening component, forming a durable spatial framework and enhancing thermal properties (thermal expansion coefficient 3.8-6.7 × 10-6 K-1).
- Processing Relevance to 6CCVD: The final processing step explicitly requires trimming the finished tiles using a diamond saw, highlighting the necessity of high-quality, durable diamond tooling, a core 6CCVD capability.
- Application: The resulting materials are suitable for high-performance, resource-conserving construction and facing applications.
Technical Specifications
Section titled âTechnical Specificationsâ| Parameter | Value | Unit | Context |
|---|---|---|---|
| Maximum Compressive Strength | 79 | MPa | Optimal composition (5*), sintered at 725 °C |
| Optimal Sintering Temperature | 725 | °C | Achieved with 10% porcelain and 5% liquid glass |
| Optimal Porcelain Content | 10 | wt. % | Used as strengthening component |
| Optimal Liquid Sodium Glass Content | 5 | wt. % | Used as flux/sintering aid |
| Optimal Cullet Fraction 1 | 35 | wt. % | 0.63-0.80 mm particle size |
| Optimal Cullet Fraction 2 | 35 | wt. % | 0.80-1.25 mm particle size |
| Optimal Cullet Fraction 3 | 30 | wt. % | 1.25-3.15 mm particle size |
| Lowest Porosity Achieved | 16.9 | % | Optimal composition (5*), sintered at 725 °C |
| Porcelain Density | 2.4-2.5 | g/cmÂł | Used as strengthening component |
| Porcelain Thermal Expansion Coeff. | 3.8-6.7 × 10-6 | K-1 | Linear thermal expansion coefficient |
| Liquid Sodium Glass Density | 1.45 | g/cmÂł | Used to reduce sintering temperature |
| Key Chemical Component (Porcelain) | 25.9 | wt. % | Al2O3 content in hard porcelain |
Key Methodologies
Section titled âKey MethodologiesâThe technology for producing the composite glass-crystal facing material is an energy-saving process focused on precise material preparation and low-temperature sintering.
- Raw Material Preparation:
- Milling of mixed glass cullet (sheet, container) in a jaw crusher.
- Milling of hard porcelain cullet in a jaw crusher, followed by fine grinding in a 10 L ball mill for two hours using uralite balls.
- Drying of liquid sodium glass in a drying oven at 105 °C for one hour, followed by fine grinding in a 6 L porcelain ball mill for 30 minutes to ensure uniform distribution.
- Fractionation and Screening:
- Crushed glass cullet is screened into three specific fractions: 0.63-0.80 mm, 0.80-1.25 mm, and 1.25-3.15 mm.
- Coarse particles (> 3.15 mm) are re-milled and re-screened.
- Batch Mixing and Compaction:
- Components (fractionated cullet, fine porcelain powder, dried sodium silicate glass) are weighed according to optimal formulations (e.g., 10 wt. % porcelain, 5 wt. % sodium silicate).
- The mixture is averaged in a paddle mixer (15 minutes).
- The mixture is stacked and compacted into 50 × 50 mm metal molds.
- Thermal Processing (Sintering):
- Compacted molds are placed in a muffle furnace for heat treatment (sintering) at temperatures ranging from 675 °C to 750 °C.
- Optimal sintering temperature was determined to be 725 °C.
- Finishing and Quality Control:
- Tiles are extracted from the molds.
- Edges are trimmed using a diamond saw (Đ°Đ»ĐŒĐ°Đ·ĐœĐŸĐč ĐżĐžĐ»ĐŸĐč).
- Finished products undergo quality control, including compressive strength and porosity testing.
6CCVD Solutions & Capabilities
Section titled â6CCVD Solutions & CapabilitiesâThe research demonstrates a need for high-precision processing and advanced material characterization, areas where 6CCVDâs expertise in MPCVD diamond materials provides critical enabling technology.
Applicable Materials
Section titled âApplicable MaterialsâTo replicate or extend this research, particularly in high-precision cutting, wear testing, and advanced thermal analysis, 6CCVD recommends the following diamond materials:
- Polycrystalline Diamond (PCD) Plates:
- Application: Manufacturing high-durability diamond saw blades and cutting tools required for the final trimming of the glass-ceramic tiles (as noted in the methodology). PCD offers superior wear resistance for abrasive materials like glass-ceramics.
- Capability Match: 6CCVD offers PCD plates up to 125mm in custom thicknesses (0.1”m - 500”m) suitable for large-format tooling inserts.
- Single Crystal Diamond (SCD) Substrates:
- Application: High-precision thermal management substrates for advanced sintering furnace components or high-temperature sensor packaging, leveraging diamondâs extreme thermal conductivity.
- Capability Match: SCD plates available in thicknesses from 0.1”m to 500”m, with superior surface quality (Ra < 1nm) for demanding thermal applications.
- Boron-Doped Diamond (BDD) Electrodes:
- Application: Electrochemical analysis of the raw materials (cullet, sodium silicate) or finished products for corrosion resistance, pH stability, and heavy metal leaching studies, leveraging BDDâs wide potential window and chemical inertness.
Customization Potential
Section titled âCustomization PotentialâThe precise nature of the material preparation (fractionation, compaction, trimming) requires highly customized tools and substrates. 6CCVD excels in providing tailored solutions:
| Research Requirement | 6CCVD Customization Solution |
|---|---|
| Diamond Saw Trimming | Custom PCD/SCD blanks and wafers for manufacturing high-precision, long-life diamond cutting tools capable of handling abrasive glass-ceramic edges. |
| High-Temperature Testing | Custom SCD substrates (up to 500”m thick) for use as stable, thermally conductive platforms in high-temperature testing rigs (e.g., measuring thermal expansion or specific heat capacity). |
| Surface Finish Requirements | SCD polishing to Ra < 1nm for optical or sensor applications; Inch-size PCD polishing to Ra < 5nm for low-friction wear parts used in mixing or compaction equipment. |
| Advanced Sensor Integration | Custom metalization (Au, Pt, Ti, W) applied directly to SCD or BDD substrates for integrating temperature sensors or strain gauges into the sintering environment. |
Engineering Support
Section titled âEngineering Supportâ6CCVDâs in-house PhD team specializes in the physics and chemistry of diamond materials and their application in extreme environments. We offer expert consultation to researchers working on similar High-Strength Composite Material projects:
- Wear Resistance Studies: Assisting in selecting the optimal diamond grade (SCD vs. PCD) for tooling used in the highly abrasive milling and cutting processes of ceramic and glass composites.
- Thermal Management: Providing guidance on using SCD as a heat spreader or substrate to ensure thermal uniformity and stability during the low-temperature sintering process (725 °C).
- Advanced Characterization: Supporting the design of high-pressure or high-temperature cells utilizing diamond anvils or windows for in situ analysis of crystallization kinetics and viscosity polytherms.
For custom specifications or material consultation, visit 6ccvd.com or contact our engineering team directly.
View Original Abstract
An effective energy-saving technology for producing composite glass-crystal facing materials based on fractionated cullet of sheet and container glasses, cullet of porcelain and sodium liquid glass has been developed. The use of fine porcelain powder in the composition of composite glass-crystal facing materials in an amount of up to 10 wt is justified. % and liquid sodium glass up to 5 wt. %. It is shown that the optimal fractional composition of granulated mixed cullet is 35 wt. % fraction 0.63-0.80 mm; 35 wt. % - fractions of 0.80-1.25 mm and 30 wt. % fraction of 1.25-3.15 mm. Polytherms of viscosity of colorless, green and brown container glasses, as well as sheet glass, are calculated. The possibility of using mixed cullet for obtaining composite glass-crystal facing materials is on the basis of obtained dependencies. The chemical composition of sheet and container glasses and porcelain is studied using x-ray fluorescence analysis. Optimal charge compositions have been developed to obtain glass-crystal materials with compressive strength up to 79 MPa. The technology of obtaining composite glass-ceramic facing material includes the following technological operations: milling of glass breakage; grinding cullet of porcelain; drying of sodium liquid glass; the screening of crushed cullet on fractions; the grind of crushed cullet of China; grinding the dried sodium silicate glass; weighing the components in accordance with the developed formulations, the averaging of the graded cullet with fine porcelain; averaging the mixture of finely ground dried sodium silicate glass; stacking the mixture in a metal mold; compaction of the mixture in metal molds; heat treatment in a muffle furnace (sintering); extraction of facing tiles from molds; trimming the edges of the tiles with a diamond saw; quality control of finished products.