CF6788 Basalt Roving for Continuous Sheet Molding (CSM)

Basalt Roving for Continuous Sheet Molding (CSM) Description

Engineered for high-performance composite reinforcement, basalt roving for CSM comprises untwisted, parallel multifilament strands of pure volcanic basalt rock, melted and extruded into continuous fibers with diameters typically ranging between 7–13 μm. These fibers are uniformly coated with a proprietary silane-based sizing agent, specifically formulated to chemically bond with unsaturated polyester (UP) and vinyl ester resins during the SMC manufacturing process. The silane treatment critically enhances fiber-resin interfacial adhesion, minimizing voids and preventing fiber dewetting while optimizing stress transfer across the composite matrix.

Inherent to basalt’s mineral composition, the roving exhibits exceptional mechanical properties: tensile strength reaches 0.60–0.65 N/tex, paired with a high elastic modulus of 91–100 GPa, significantly surpassing E-glass in rigidity and fatigue resistance. Despite this strength, fibers retain 2.6–3.1% elongation at break, enabling controlled energy absorption without brittle fracture. Thermally, basalt roving remains dimensionally stable across extremes (–260°C to +650°C), resisting softening during SMC’s high-pressure molding cycles while imparting flame retardancy and corrosion immunity to end products.

Linear density—calibrated between 180–2400 Tex (with 800–1200 Tex being optimal for SMC)—ensures consistent choppability and homogeneous dispersion within resin pastes. This facilitates uniform load distribution and eliminates clustering defects. Electrically non-conductive yet highly resistant to alkalis, acids, and UV degradation, basalt roving synergizes with polymer matrices to yield lightweight composites with superior flexural strength, impact toughness, and long-term durability—ideal for automotive panels, electrical enclosures, and infrastructure components demanding rigorous mechanical and environmental resilience.

Basalt Roving for Continuous Sheet Molding (CSM) Applications

Basalt roving engineered for CSM is extensively used across industries requiring lightweight, high-strength composites. In automotive manufacturing, it reinforces SMC components like body panels, bumpers, and underbody shields, reducing vehicle weight while enhancing crash resistance and corrosion durability, critical for electric vehicle battery housings. The construction sector leverages its alkali resistance in concrete reinforcement grids, seismic retrofit fabrics, and façade panels, where thermal stability (–260°C to +650°C) ensures performance in extreme climates.

For renewable energy, basalt-CSM composites form wind turbine nacelles and blade stiffeners, capitalizing on the material’s fatigue resistance and vibration-damping. In electrical engineering, its non-conductive nature and flame retardancy (LOI >68%) suit switchgear enclosures and insulator cores. Industrial applications include chemical storage tanks, piping systems, and conveyor belts, where acid/UV resistance outperforms traditional materials.

Emerging uses span aerospace interiors (overhead bins, flooring) and marine composites (hulls, decks), exploiting basalt’s saltwater immunity. Crucially, its compatibility with UP/vinyl resins allows seamless integration into automated SMC lines, enabling mass production of complex geometries with consistent fiber dispersion. Sustainability-driven sectors also adopt basalt roving as an eco-friendly alternative to glass/carbon fibers, reducing lifecycle CO₂ by 30–50% while maintaining recyclability.

Basalt Fiber Yarn Packaging

Our products are packaged in customized cartons of various sizes based on the material dimensions. Small items are securely packed in PP boxes, while larger items are placed in custom wooden crates. We ensure strict adherence to packaging customization and the use of appropriate cushioning materials to provide optimal protection during transportation.

Packaging: Carton, Wooden Box, or Customized.

Kindly review the packaging details provided for your reference.

Manufacturing Process

1.       Testing Method

(1)    Chemical Composition Analysis - Verified using techniques such as GDMS or XRF to ensure compliance with purity requirements.

(2)    Mechanical Properties Testing - Includes tensile strength, yield strength, and elongation tests to assess material performance.

(3)    Dimensional Inspection - Measures thickness, width, and length to ensure adherence to specified tolerances.

(4)    Surface Quality Inspection - Checks for defects such as scratches, cracks, or inclusions through visual and ultrasonic examination.

(5)    Hardness Testing - Determines material hardness to confirm uniformity and mechanical reliability.

Please refer to the SAM testing procedures for detailed information.

Basalt Roving for Continuous Sheet Molding (CSM) FAQs

Q1. What is Basalt Roving for CSM?

A silane-coated, untwisted basalt fiber bundle engineered for reinforcing unsaturated polyester/vinyl resins in Continuous Sheet Molding Compounds (CSM). It's chopped and dispersed into resin pastes for high-volume composite production.

Q2: Why choose basalt over glass/carbon fiber in SMC?

Basalt offers:

Higher temperature resistance (–260°C to +650°C)

Superior chemical/UV stability (resists acids/alkalis)

Better mechanical properties (0.65 N/tex strength, 100 GPa modulus)

Eco-friendly profile (30-50% lower CO₂ vs. glass fiber)

Q3: How is it processed in SMC?

Roving is:

Chopped (typically 25-50 mm lengths)

Blended with resin/fillers (e.g., UP, vinyl ester, CaCO₃)

Compression-molded under heat/pressure into parts.

Key advantage: Silane sizing ensures rapid wet-out and uniform dispersion.

Related Information

1.       Common Preparation Methods

The manufacturing of basalt roving for CSM begins with the selection of high-purity volcanic basalt rock, which is rigorously washed, crushed, and sorted into uniform granules. These raw materials are fed into gas- or electric-powered furnaces operating at approximately 1,450–1,500°C, where they undergo complete melting into a homogeneous lava-like state. The molten basalt is then gravity-fed through platinum-rhodium alloy bushings pierced with hundreds of micro-nozzles (typically 7–13 μm in diameter), where controlled extrusion transforms the melt into continuous filaments under high tension. As the nascent fibers emerge, they are rapidly quenched with water-based coolants to lock in the amorphous molecular structure critical for mechanical strength.

Immediately after formation, the filaments pass through an aqueous sizing bath containing a proprietary silane-based coupling agent—often a blend of γ-aminopropyltriethoxysilane (APS) and epoxy-functionalized silanes—which uniformly coats each filament via dip-roll application. This sizing not only protects fibers from abrasion during downstream processing but also functionalizes their surface with reactive groups designed to chemically bond with unsaturated polyester and vinyl ester resins during composite fabrication. The coated filaments are then gathered into parallel, untwisted bundles through precision guides, with linear density calibrated between 180–2,400 Tex (adjusted via filament count and draw speed).

The assembled rovings undergo controlled drying in infrared ovens to evaporate solvents while crosslinking the sizing chemistry, followed by high-speed winding onto perforated polymer bobbins under constant tension. Throughout this process, automated laser gauges monitor filament diameter consistency, while electrostatic sensors detect sizing coverage uniformity. Final quality assurance includes testing for tensile strength (≥0.60 N/tex), fuzz resistance, and resin wettability—validating readiness for chopping and dispersion into SMC compound formulations optimized for automotive, construction, and electrical applications demanding thermal stability and corrosion resistance.