ISO 7384:1986 PDF

Overview

ISO 7384:1986 - "Corrosion tests in artificial atmosphere - General requirements" specifies general requirements for laboratory corrosion tests carried out in controlled/accelerated artificial atmospheres. The standard covers specimen types, apparatus and procedural controls for testing metals and alloys with or without permanent or temporary corrosion protection. ISO 7384 is intended as a baseline for other international test methods, accelerated testing procedures and for the design/construction of corrosion chambers.

Key topics and technical requirements

• Scope and classification: Defines three test types - optimized (simulate service mechanism accelerated), short‑term (comparative accelerated), and rapid quality‑control tests.
• Specimens: Consistent shape, dimensions and surface condition; preferred thickness 0.5–3 mm; minimum total specimen area normally ≥ 25 cm²; cut edges to be deburred and usually protected unless edge effects are under study.
• Chamber and apparatus:
  • Chambers must ensure homogeneous, uniform exposure; upper chamber profile prevents condensate dripping onto specimens.
  • Humidification using distilled or de‑ionized water only; humidity ramp to target ≤ 1 hour.
  • Temperature/humidity control accuracy: ±2 °C and ±5 % RH.
  • Air circulation to equalize conditions; materials in contact with corrosive agents must be resistant.
  • Avoid cross‑contamination (e.g., volatile corrosion inhibitors require dedicated chambers).
  • Maximum specimen surface area guideline: 0.75 m² per m³ of chamber volume.
• Exposure and monitoring:
  • Recommended exposure durations include 24, 48, 96, 240, 480, 720, 2016 hours depending on objective.
  • Records of temperature, relative humidity and active corrosive agent concentrations should be automatic or periodic.
• Measurements and evaluation:
  • Evaluation criteria include visual appearance, time to first corrosion, number/distribution of defects, mass change (ISO 8407 referenced), dimensional and property changes.
  • Weighing precision: ±0.001 g for specimens ≤ 200 g; ±0.01 g for heavier specimens.
• Test report: Must include test purpose, method, specimen description, exposure conditions, measurements and evaluation criteria.

Applications and users

ISO 7384 is used by:

• Corrosion testing laboratories and R&D teams conducting accelerated corrosion assessments
• Manufacturers of metals, alloys and protective coatings for qualification and comparative testing
• Quality‑control and failure‑analysis engineers
• Designers and builders of corrosion chambers seeking baseline design and control requirements
• Standards committees referencing general requirements in specific corrosion test methods

Related standards

Standards referenced in ISO 7384 include (examples):

• ISO 8407 (removal of corrosion products)
• ISO 3768 / ISO 3763 / ISO 3770 / ISO 4536 (various salt/spray and spray distribution tests)
• ISO 1456 / ISO 1458 / ISO 1461 / ISO 2081 / ISO 2082 (metallic coatings)
• ISO 4623 (filiform corrosion) Consult these for method‑specific procedures and evaluation methods.

Keywords: ISO 7384:1986, corrosion tests, artificial atmosphere, corrosion chambers, accelerated corrosion testing, metals and alloys, specimen preparation, evaluation criteria.