What is mineral fibre?

Per GB/T 4132-1996, man-made mineral fibres are the general term for inorganic fibres made from rock, slag, glass, metal oxides or porcelain clay. Boer products are made mainly from natural rocks such as diabase, basalt and dolomite, processed by melting, wet-process purification and surface treatment.

What does Boer's wet process mean?

Raw materials are melted in a cupola furnace and fibreised by a four-roll centrifugal spinner. Fibres are separated from shot in the settling chamber, then collected by hub collectors, purified, dried and packaged. The water medium eliminates electrostatic attraction between fibres and shot, and separates them by their different gravity and drag in motion.

What is shot content and how is it controlled?

Shot refers to non-fibrous material in the fibre (usually counted above 125 μm). Boer separates fibre from shot in the settling chamber through the wet process; some models control non-fibrous content below 1%. Specific values are subject to the batch test report.

Melting point and heat resistance?

Standard models have a melting point above 1000 ℃; the white-fibre series (e.g. BE-B03, BE-B07, BE-C08) has a melting point above 1600 ℃. Specific values are subject to the batch test report.

Dispersibility and resin bonding?

The wet process gives a more uniform surface treatment; the fibre is hydrophilic and easy to disperse, bonding well with phenolic resin, and is suitable for friction and sealing material formulations.

Does Boer fibre contain asbestos?

No. Boer products are asbestos-free man-made mineral fibres and have passed SGS asbestos testing (report CANEC25025290506, 2025-10-22); all 6 asbestos types, including chrysotile, were not detected (XRD/PLM, detection limit 0.1%).

Is Boer fibre RoHS/SVHC compliant?

Yes. Products have passed RoHS 10-substance testing (CANEC25025290502) and SVHC 250-substance testing (CANEC25025290504), complying with applicable REACH requirements.

Is an MSDS/SDS available?

Yes. Boer can provide MSDS/SDS prepared in accordance with REACH Annex II (e.g. EECSSDS2605060802), and the batch test report is delivered with each shipment.

What are the packaging and storage requirements?

Normally moisture-proof laminated bags or eco-friendly paper bags, with custom packaging on request. Store in a dry, ventilated place away from moisture, open flame and strong oxidizers.

How can I select a product and contact Boer?

Call the national sales hotline 4006-0763-82 or email info@boerfibre.com. Boer provides selection advice, samples and batch test reports.

Introduction to mineral powders

Category Raw Materials Published 2026-03-31 Source www.boerfibre.com

Abstract

This reprinted article introduces mineral powders used in friction materials, listing main component, hardness, density, melting/boiling point, mesh and pass rate. Examples include chromite powder (Cr₂O₃ 30–40%, Mohs 5.5, density 5.09 g/cm³, mp 1890 ℃), pyrite powder (FeS₂ 60–75%, density 4.9–5.2 g/cm³, mp 1193 ℃), molybdenite powder (MoS₂, density 4.7–5.0, Mohs 1, mp 1185 ℃, friction coefficient 0.07–0.1), lead-zinc sulfide powder (PbS+ZnS >40%), magnetite powder (Fe₃O₄ >85%, mp 1539 ℃), hematite powder (Fe₂O₃ >80%), wollastonite powder (CaSiO₃, density 2.8–3.1, mp 1540 ℃), garnet, feldspar (K₂O+Na₂O >11%), quartz (SiO₂ >98.5%, Mohs 7, density 2.65, mp 1730 ℃), barite (BaSO₄ >92%, density 4.3–4.5) and zeolite.

Most products are supplied at 200 or 325 mesh with about 97–98% sieving pass, and are used to adjust high-temperature friction coefficient, improve wear resistance, strengthen bonding and lower cost in disc/drum brake pads and clutch facings.

Key facts

Scope: mineral powders for friction materials (reprinted compilation)
Common sizes: 200 / 325 mesh; about 97–98% pass rate
Main-component examples: chromite Cr₂O₃ 30–40%; pyrite FeS₂ 60–75%; magnetite Fe₃O₄ >85%; hematite Fe₂O₃ >80%; quartz SiO₂ >98.5%; barite BaSO₄ >92%; wollastonite CaSiO₃; molybdenite MoS₂
Molybdenite: density 4.7–5.0; Mohs 1; mp 1185 ℃; friction coefficient 0.07–0.1
Functions cited: adjust high-temperature friction coefficient, reduce fade, improve bonding/strength, lower cost
Typical applications: disc pads, drum pads, clutch facings

The original article is in Chinese; see the Chinese version for the full text. This page provides the English title, abstract and key facts only — translated and compiled from the original, without full verbatim translation.

Introduction to mineral powders

Abstract

Key facts

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