ASTM B117 Standard Practice for Operating Salt Spray (Fog) Apparatus

ASTM B117 Salt Spray Testing for Xylan coating.

Xylan 1070/1424 coating is widely for stud bolt

Xylan® 1424 coating applied over a zinc phosphate steel can exceed 1500 hours of ASTM B117 salt fog test.

Xylan 1070 is an Organic solvent based, low friction coating normally used over Zinc, Phosphate or other pretreatment to achieve up to 3000 hours salt spray.

astm-b117 is a widely used standard issued by ASTM International for evaluating the corrosion resistance of coatings, materials, and products exposed to a saline environment. It defines the procedures for conducting a neutral salt spray (NSS) test, which is a controlled accelerated corrosion test.

ASTM B117 Salt Spray Corrosion Testing is used primarily to compare the corrosion resistance of painted or metal coated samples. The test has been used for almost 100 years, and has been standardized as ASTM B117 since 1939.

Salt Solution: A standard ASTM B117 salt solution consisting of 5 parts (by weight) of sodium chloride to 95 parts water is prepared. The water used in this testing is compliant with the ASTM D1193 Specification for Reagent Water, Type IV.

pH Range: 6.5 to 7.2

Test Temperatures: The exposure zone is to be kept at 35 +/- 2°C (95+/- 3°F). The temperature in the saturation (bubble) tower is to be kept between 46 and 49°C (114-121°F).

Test Cycle: ASTM B117 is a continuous spray (fog) test.

Test Duration: Tests can range from <24 hours to thousands of hours depending upon the material being tested.

Key Features of ASTM B117

  1. Test Solution:
    • A solution of sodium chloride (NaCl) dissolved in distilled or deionized water.
    • Concentration: 5% NaCl by weight.
    • pH: Adjusted to 6.5–7.2.
  2. Test Chamber Conditions:
    • Temperature: Maintained at 35°C ± 2°C (95°F ± 3.6°F).
    • Relative Humidity: Saturated environment within the test chamber.
  3. Spray Application:
    • Salt solution atomized using compressed air.
    • Fog collection rate: 1–2 mL/hour per 80 cm² (12.4 in²).
  4. Specimen Placement:
    • Samples must be oriented at an angle of 15° to 30° from vertical.
    • No overlapping or contact between specimens to allow uniform exposure.
  5. Test Duration:
    • Duration depends on specific requirements or standards for the material or coating being tested.
    • Common durations: 24, 48, 96, 500, or 1000 hours.3000 hours.

Related Standards

  1. ISO 9227: International standard for salt spray testing, similar to ASTM B117.
  2. ASTM D610: Evaluates degree of rusting on painted steel surfaces.
  3. ASTM G85: Modified salt spray tests for specific environments.