Overview
ISO 14656:1999 specifies requirements for epoxy powders and sealing materials used to produce fusion-bonded epoxy coatings on steel used for concrete reinforcement (rebar, wire, welded fabric). The standard defines two coating classes - flexible (Type A) and non‑flexible (Type B) - and sets performance tests and acceptance criteria to ensure adhesion, moisture and chemical resistance, and durability of coated reinforcement.
Key Topics
- Scope and materials
- Thermosetting epoxy powder formulations for fusion-bonded epoxy coatings.
- Sealing material compatible with the epoxy coating, inert in concrete, for repair of cut ends and damaged areas.
- Coating classification
- Type A (flexible) and Type B (non‑flexible) coatings; formulation choices can increase adhesion/moisture resistance but may reduce flexibility.
- Performance tests and requirements
- Chemical resistance: immersion in simulated environments (deionized water, 3% NaCl, alkaline solutions) - 28 days at 55 °C with measured disbondment limits (average maximum disbondment for 95% of bars ≤ 4 mm).
- Cathodic disbondment: 168 h test under applied potential (polarized potential around −1 500 mV vs calomel electrode); average disbondment radius acceptance ≤ 2 mm.
- Salt spray resistance: 800 h in 5% NaCl spray at elevated temperature; acceptance criteria for disbondment radius ≤ 3 mm.
- Chloride permeability: 45‑day barrier test using two‑compartment cell and cured epoxy films to evaluate chloride transport.
- Normative references: includes relevant test standards such as ISO 6272 and ISO 9352.
Applications
- Manufacturers of fusion‑bonded epoxy coated rebar, wire and welded fabric - specification and QC of epoxy powder formulations and sealing systems.
- Construction and structural engineers / specifiers - selecting coated reinforcement that meets defined corrosion‑protection performance for reinforced concrete structures.
- Laboratories and QA/QC personnel - performing standardized tests (chemical immersion, cathodic disbondment, salt spray, chloride permeability) and verifying acceptance criteria.
- Contractors and fabricators - guidance on repair sealing material and handling of coated reinforcement on site.
Using ISO 14656 helps ensure durable corrosion protection for steel reinforcement, reduces chloride ingress and disbonding risks, and provides clear acceptance tests for procurement and quality control.
Related Standards
- ISO 6272:1993 - Paints and varnishes - Falling weight test
- ISO 9352:1995 - Plastics - Determination of resistance to wear by abrasive wheels
Keywords: ISO 14656:1999, epoxy powder, fusion-bonded epoxy coating, sealing material, coated rebar, cathodic disbondment, salt spray, chloride permeability, reinforcement corrosion protection.