What are the differences in applications and performance between surface felt and ordinary fiberglass felt?
I. Raw Materials and Structure: Thin and Uniform vs. Thick and Strong
Fiberglass surface mat is a thin mat specifically for surface layers, commonly with a basis weight of 20g/㎡, 30g/㎡, or 50g/㎡. It features extremely fine, uniformly dispersed fibers, a soft texture, and is formed using a wet-process method. Its thinness and controllable breathability, along with excellent moldability, make it particularly suitable for complex curved surfaces and irregularly shaped components.
Ordinary fiberglass mat typically refers to chopped strand mat, with a basis weight commonly ranging from 150g to 450g. It is formed by randomly laying and bonding short chopped fiberglass fibers of a certain length. The fibers are coarser, the basis weight is higher, and the structure is looser. Its core function is to provide structural strength and rigidity, serving as the main material for the reinforcing layer.
Structural differences directly determine performance: surface mats can quickly absorb resin, forming a smooth surface with a high resin content; ordinary mats, on the other hand, are primarily composed of a fiber skeleton, responsible for bearing the load.
II. Core Performance Differences: Appearance & Corrosion Resistance vs. Strength & Structure
1. Surface Finish
Surface Felt: After molding, it has no fiber texture, pinholes, or pitting, resulting in a high degree of surface smoothness. It can be directly used as a gel coat reinforcement material, significantly improving the aesthetics of the product.
Ordinary Fiberglass Felt: The surface is rough with obvious fiber texture, making it unsuitable for direct surface finishing. It must be used in conjunction with a surface layer material.
2. Resin Impregnation & Resin Content
Surface Felt: Resin impregnates quickly and evenly, achieving a resin content of over 80% after molding, forming a dense resin protective layer with outstanding corrosion resistance, seepage prevention, and weather resistance.
Ordinary Fiberglass Felt: Contains moderate resin content, primarily fiber-reinforced, focusing on structural mechanical properties.
3. Mechanical Strength
Surface Felt: Lower strength, not used for main load-bearing structures, only for surface protection and aesthetics.
Ordinary Fiberglass Felt: Offers stronger tensile, bending, and impact resistance, making it the primary reinforcement material for fiberglass pipes, tanks, shells, and structural components.
4. Chemical Resistance and Weather Resistance
Surface Felt: The resin layer isolates corrosive media, providing acid and alkali resistance, water resistance, and aging resistance, significantly extending product lifespan.
Ordinary Fiberglass Felt: Corrosion resistance depends on the overall composite system; without surface protection, it is prone to aging and water seepage.
In short: Surface Felt = Aesthetics + Protection; Ordinary Fiberglass Felt = Reinforcement + Load-bearing Capacity.
III. Typical Application Scenarios: Clear Division of Labor, No Substitution
**Fiberglass Surface Mat Application Scenarios:**
- Surface layer of fiberglass products: pipes, tanks, ship hulls, bathroom fixtures, wind turbine blade shells
- Curved components with high requirements for appearance and corrosion resistance
- Battery pack shells, interior trim, lightweight cladding materials for new energy vehicles
- Building insulation, anti-corrosion veneers, thin insulating layers for electronics
**Ordinary Fiberglass Mat Application Scenarios:**
- Structural reinforcement layer: fiberglass tanks, profiles, covers, mold substrates
- General-purpose products with high strength requirements
- Low-cost mass-produced components
- Structural components for construction, chemical industry, and general machinery
Many high-quality products use a composite structure of surface mat + ordinary fiberglass mat: the surface mat ensures appearance and corrosion resistance, while the intermediate mat ensures strength, offering excellent cost-effectiveness and performance.
IV. Understanding the Logic of High-End Material Selection in New Energy Vehicles: Taking the Zhiji LS9 as an Example
With the upgrading of new energy vehicles towards lightweighting, safety, and high-end features, the application of fiberglass materials is becoming increasingly crucial. Popular models such as new energy vehicles extensively use fiberglass composite materials in body panels, battery pack protection, interior substrates, and chassis skid plates. The appropriate combination of surface felt and ordinary fiberglass felt directly determines the quality of components.
In the battery pack upper shell and lightweight coverings, surface felt is typically used as the surface layer to improve surface smoothness, sealing, and weather resistance, while reducing wind resistance and enhancing the appearance. The interior uses ordinary fiberglass felt or composite felt for structural reinforcement, ensuring impact resistance, vibration resistance, and lightweight safety protection. This combination meets the insulation, flame retardant, and lightweight requirements of the 800V high-voltage platform while also improving the overall refinement and durability of the vehicle.
In short, in new energy vehicle manufacturing, surface felt determines the high-end feel, while ordinary fiberglass felt determines structural safety; both are indispensable. This is why more and more automakers and parts manufacturers are beginning to strictly distinguish between the two materials, no longer using them interchangeably or interchangeably.
V. Procurement and Production Selection Recommendations
1. For those prioritizing appearance, corrosion resistance, and weather resistance: prioritize fiberglass surface mat, with a recommended basis weight of 30g-50g.
2. For those prioritizing strength, structure, and low cost: prioritize ordinary fiberglass chopped strand mat, with the basis weight selected based on the load.
3. For high-end products and new energy vehicle components: adopt a composite solution of surface mat + ordinary mat.
4. For mass production and complex curved surfaces: surface mat has better mold adhesion, which can improve yield and reduce rework.
5. Pay attention to industry trends: Wind power, photovoltaics, and new energy vehicles continue to drive demand for high-quality surface mats; early investment in high-quality materials can enhance product competitiveness.
Fiberglass surface mat and ordinary fiberglass mat may seem similar, but they actually have different functions and performance characteristics. Surface mat is responsible for aesthetics and protection, while ordinary fiberglass mat is responsible for strength and structure. In today's rapidly developing composite materials industry and booming high-end sectors such as new energy vehicles, proper differentiation and scientific matching can not only stabilize quality and reduce costs, but also seize the material upgrade opportunities brought by popular new energy vehicles such as the Zhiji LS9. Only by selecting the right materials and using the right processes can we create more competitive products and gain an advantage in industry competition.
