As an important high-performance material, glass fiber has developed into one of the basic materials of modern industry since its industrial production in the 20th century. This article systematically introduces the development history, chemical composition and classification, production process, physical and chemical performance characteristics, main application areas, market status and future development trends of glass fiber. Through in-depth analysis of the entire glass fiber industry chain, it aims to provide comprehensive technical references and market insights for relevant industry practitioners, researchers and purchasing decision makers.
1. Introduction
Fiberglass is an inorganic non-metallic material made of glass by high-temperature melting and drawing. In 1938, Owens-Corning of the United States first achieved industrial production of fiberglass, marking the beginning of the modern composite material era. After more than 80 years of development, fiberglass has evolved from a single insulating material to a multifunctional material widely used in construction, transportation, electronics, energy and other fields.
Compared with traditional metal materials, fiberglass has significant advantages such as low specific gravity, high strength, corrosion resistance and good insulation. With the advancement of composite material technology, glass fiber reinforced plastics (GFRP) have gradually replaced metal materials in many fields and become an important choice for achieving lightweight, energy saving and environmental protection. According to data from Lucintel, a global market research organization, the global fiberglass market size will reach approximately US$15 billion in 2022, and is expected to exceed US$20 billion by 2027, with an annual compound growth rate of approximately 5.8%.
This article will comprehensively analyze the manufacturing technology, performance characteristics and application status of glass fiber, and explore its development prospects in emerging fields such as new energy and 5G communications, providing valuable reference information for related industries.
2. Classification and chemical composition of glass fiber
2.1 Classification by chemical composition
The performance of glass fiber depends largely on its chemical composition. According to the different oxide compositions, it is mainly divided into the following categories:
E-glass fiber (electrical grade):
Composition: SiO (52-56%), AlO (12-16%), CaO (16-25%), MgO (0-5%), BO (5-10%)
Features: excellent electrical insulation, balanced mechanical properties
Application: circuit boards, electrical insulation materials
C-glass fiber (chemical grade):
Composition: high SiO (60-65%), added ZrO, etc. Corrosion-resistant ingredients
Features: Excellent acid and alkali resistance
Applications: Chemical pipelines, tank linings
S-glass fiber (high-strength grade):
Composition: High AlO (20-25%), MgO (10-15%)
Features: Tensile strength is 30-40% higher than E-glass
Applications: Aerospace, military equipment
AR-glass fiber (alkali-resistant grade):
Composition: Added ZrO (16-20%)
Features: Resistance to cement alkali corrosion
Applications: GRC building reinforcement materials
2.2 Classification by product form
Continuous fiber: used for woven fabrics, belts, etc.
Chopped fiber: 3-50mm in length, used to reinforce plastics
Glass wool: used for thermal insulation materials
3. Glass fiber production process
3.1 Raw material preparation
The main raw materials include:
Quartz sand (SiO source)
Limestone (CaO source)
Calebrite (BO source)
Soda ash (NaCO, flux)
The raw materials must be strictly screened to control the content of impurities such as FeO to less than 0.1% to ensure the stable performance of the final product.
3.2 Melting process
Modern glass fiber production mainly adopts two melting processes:
Pool kiln method (direct melting method):
Raw materials are directly added to the pool kiln, and the temperature is controlled at 1560-1600
Advantages: low energy consumption (30% energy saving compared with the crucible method), suitable for large-scale production.
More than 90% of the global production capacity adopts this process.
Crucible method:
First make glass balls, then melt and draw wires.
Advantages: suitable for small batch and multi-variety production.
Disadvantages: high energy consumption, low production efficiency.
3.3 Fiber Forming
The molten glass is drawn through a platinum-rhodium alloy plate (containing 400-8000 nozzles) at a drawing speed of 3000-5000 m/min. During the forming process, the following must be precisely controlled:
Temperature fluctuation (±1°C)
Glass viscosity (1000-1500 poise)
Cooling rate (>1000°C/s)
3.4 Surface treatment
During the drawing process, a wetting agent needs to be applied. Its main functions are:
Protect the fiber from mechanical damage
Improve the adhesion with the resin
Give the fiber special properties such as antistatic
Modern wetting agents are mostly composite formulas, including:
Film formers (epoxy, polyester, etc.)
Coupling agents (silanes)
Lubricants
Antistatic agents
4. Performance characteristics of glass fiber
4.1 Physical properties
Density: 2.5-2.7g/cm³ (only 1/4 of steel)
Tensile strength: 3.0-4.8GPa (E-glass)
Elastic modulus: 72-86GPa
Thermal expansion coefficient: 5.0×10/ (close to concrete)
4.2 Chemical properties
Acid resistance: C-glass loses weight in 20% HSO <0.5mg/cm²·d
Alkali resistance: AR-glass retains strength >85% in NaOH solution
Weather resistance: Strength retention >90% after UV aging for 1000h
4.3 Comparison with other fibers
Performance indicators | E-glass | S-glass | Carbon fiber | Aramid fiber |
Density (g/cm³) | 2.54 | 2.49 | 1.78 | 1.44 |
Tensile strength (GPa) | 3.4 | 4.6 | 3.5-7.0 | 3.0-3.6 |
Modus (GPa) | 72 | 86 | 230-600 | 70-130 |
Elongation at break (%) | 4.8 | 5.4 | 1.5-2.0 | 2.5-3.5 |
Price ($/kg) | 1.5-2.5 | 8-12 | 15-150 | 20-50 |
5. Application areas of glass fiber
5.1 Construction field (accounting for 35% of global consumption)
GRC curtain wall panels: using AR-glass, the thickness can be reduced to 8-10mm
Building reinforcement: carbon/glass hybrid fiber cloth, tensile strength>1000MPa
Waterproof material: glass fiber base modified asphalt roll
5.2 Transportation (accounting for 28%)
Automotive parts: spare tire compartment made of GMT material, 40% weight reduction
Railway transportation: FRP body, meeting EN45545 fire protection standard
Shipbuilding: vacuum infusion hull, reducing weld corrosion
5.3 Electronics and electrical (18%)
High-frequency PCB: low dielectric glass fiber cloth (Dk<4.5)
Insulation material: high temperature resistant mica tape (H grade 180)
5G antenna cover: wave-transmitting composite material
5.4 Energy and environmental protection (12%)
Wind turbine blades: high modulus glass fiber is used for blades above 80m
Flue gas treatment: glass fiber filter bags, temperature resistant to 260
Hydrogen energy storage tanks: glass fiber wrapping layer for type IV bottles
5.5 Other applications (7%)
Sports equipment: carbon/glass hybrid golf clubs
Medical equipment: X-ray-penetrable FRP stretchers
Aerospace: secondary load-bearing structural parts
6. Global market analysis
6.1 Capacity distribution
Major global manufacturers:
China Jushi (annual capacity of 2 million tons)
US OCV (1.5 million tons)
Japan NEG (800,000 tons)
Chongqing International (600,000 tons)
China accounts for more than 65% of the world's total capacity, of which Tongxiang, Zhejiang is the world's largest production base.
6.2 Price trend
Average market price in 2023:
Direct yarn: 6,000-8,000 yuan/ton
Electronic yarn: 9,000-12,000 yuan/ton
High modulus yarn: 15,000-20,000 yuan/ton
Affected by energy costs, European product prices are 20-30% higher than those in Asia.
6.3 Trade pattern
Major exporting countries: China, the United States, Egypt
Major importing countries: India, Germany, Mexico
The Sino-US trade friction has led to the United States imposing a 25% tariff on Chinese glass fiber products.
7. Technology development trends
7.1 High performance
Ultra-high strength glass fiber (strength>5GPa)
Low dielectric glass fiber (Dk<4.0)
High temperature resistant glass fiber (softening point>800)
7.2 Intelligent manufacturing
Digital twin technology optimizes pool kiln energy consumption
AI visual inspection of fiber defects
Automated logistics system
7.3 Green production
Boron-free glass formula (reduce BO usage)
Waste fiber recovery rate increased to 95%
Development of bio-based impregnating agents
8. Conclusion and Outlook
The glass fiber industry is facing an important transition period:
New energy fields (wind power, hydrogen energy) will become the largest growth point
5G communication drives the demand for low-dielectric products
Environmental protection regulations are tightening, forcing green manufacturing to upgrade
It is estimated that by 2030, the global market size will reach US$28 billion, of which the Asian market will account for more than 70%. Chinese companies should increase R&D investment, break through the technical barriers of high-end products, and realize the transformation from a "manufacturing power" to a "manufacturing power".
