Overview
EN ISO 10081-4:2014 - "Classification of dense shaped refractory products - Part 4: Special products" (ISO 10081-4:2014) is the CEN/ISO standard that defines how to classify and designate dense shaped special refractory products of non-standard or mixed compositions. It is part 4 of the ISO 10081 series and complements Parts 1–3 by covering oxide, non‑oxide and mixed systems such as alumina‑chromia, zirconia‑silica, silicon carbide and carbon‑based refractory shapes.
Key topics and technical requirements
- Scope and product types: Covers special compositions including oxide products, oxide/non‑oxide combinations, non‑oxide (SiC, C) products, and designated-only types (e.g., borides, nitrides).
- Six classification criteria:
- Type of product (e.g., ACr, ZS, AZS, SiC, C, AC, AMC, AFC, ASC, ZC)
- Group determined by mass‑fraction ranges of main chemical components (tables define specific ranges and designations such as ACr90/5, Z95, AZS70/2, etc.)
- Principal raw material(s) (including stabilizers like those for zirconia)
- State of the raw materials
- Nature of the bond (e.g., chemical/physical bonding agents)
- Post‑treatment (heat treatment, impregnation, surface finishes)
- Chemical analysis basis: Classification is normally based on analysis of calcined products using standards such as ISO 12677.
- Carbon content notation: For carbon‑containing products residual carbon after coking is reported using group indices (N) and antioxidant additives are indicated by appending “A” to group classification.
- Designation rules: The standard prescribes how to form product designations that communicate composition and group.
Applications
- Standardizes naming and classification for dense shaped refractories used in:
- Steel and non‑ferrous metallurgy linings
- Glass and ceramics kilns
- Petrochemical and high‑temperature industrial furnaces
- Foundries and incineration systems
- Helps suppliers, purchasers, and engineering teams specify the correct refractory shapes by composition and performance‑relevant chemistry.
- Assists testing laboratories and quality managers in interpreting material certificates and ensuring compliance with contractual specifications.
Who should use this standard
- Refractory manufacturers and product developers
- Materials and process engineers in high‑temperature industries
- Quality assurance professionals, labs performing chemical analysis (ISO 12677)
- Procurement and specification writers for industrial furnaces and linings
- Standards bodies and conformity assessment organizations
Related standards
- ISO 10081 series (Parts 1–3): alumina‑silica and basic products
- ISO 12677: methods for chemical analysis of calcined refractory products
Using EN ISO 10081-4:2014 supports consistent classification, clearer specifications, and improved communication across supply chains for complex refractory materials.
