ASTM B117 Operating Salt Spray (Fog) Apparatus

Get Certified ASTM B117 Testing for Reliable Corrosion Testing

The ASTM B117 standard helps manufacturers maintain standards, verify suppliers, check coating quality, and demonstrate compliance during inspections. Manufacturers and coating applicators use ASTM B117-certified tests to check coating durability, evaluate corrosion-inhibiting treatments, and filter out materials before they are subjected to the field. Certification enhances customer confidence by providing reliable, verifiable international testing that supports material performance claims. For more information about ASTM B117, consult MaTestLab.

• Provides specifications of materials or products.
• Applies to metals, coatings, and other materials exposed to a controlled salt-fog environment.
• Specifies conditions for operating the salt spray chamber and testing apparatus.
• Provides a standardized method for conducting salt spray (fog) testing.
• Evaluates the corrosion resistance of metallic and coated specimens.
• Assesses corrosion performance and coating quality under accelerated laboratory conditions.
• Supports quality control and comparative evaluation of corrosion-resistant materials.

What are the Uses of ASTM B117 Standard?

ASTM B117 is a standardized test method used to evaluate the relative corrosion resistance of metals and surface coatings by exposing them to an accelerated salt spray (fog) environment. Engineers benchmark products to see how different platings, paints, powder coats, or surface treatments perform relative to one another under identical corrosive conditions. The ASTM B117 standard-

• Improves quality monitoring by detecting coating defects such as pores, cracks, or poor bonding.
• Measures the resistance of metals and coated materials 
• Helps to enhance corrosion protection mechanisms.
• Compares the performance of protective coatings like paints, platings, and galvanizing.
• Helps manufacturers comply with regulatory and customer requirements on corrosion durability.
• Provides enhanced corrosion information for real-time research, material selection, and warranties.

Which materials are tested under the ASTM B117 standard?

The ASTM B117 standard evaluates the corrosion resistance of metallic materials and surface coatings. Commonly tested metals and alloys include carbon and alloy steel, stainless steel, aluminum and aluminum alloys, galvanized steel, and copper and copper-based alloys. Tested surface coatings and treatments include plated components, painted and powder-coated parts, Anodized finishes, fasteners, and hardware components.

Why is ASTM B117 important?

ASTM B117 is important because it serves as the global benchmark for evaluating how well materials and coatings resist corrosion. Material standardization, rapid quality control, and materials benchmarking are key factors engineers and manufacturers use to ensure and develop quality products. 

ASTM B117 Testing Process and Data Collection

The analyst selects representative specimens for evaluation. Technicians clean and prepare the specimens and put them in the salt spray chamber at the specified angle. The chamber produces a continuous salt fog under controlled temperature, salt concentration, and fog collection conditions. Technicians expose the specimens for the specified time duration and monitor the chamber conditions throughout the test. After exposure, technicians remove and evaluate the specimens for corrosion, rust, or other visible changes and record observations according to applicable requirements. 

Common Challenges and Troubleshooting

Troubleshooting concerns include checking chamber calibration, cleaning atomizing nozzles, ensuring proper solution concentration, maintaining temperature stability, ensuring a clean water supply, and positioning the specimen correctly. Untidy pre-test cleaning can cause incorrect corrosion patterns, and leaking corrosion chambers can change the fog density. Testing is carried out under an atmosphere of continuously exposed salt mist on specimens. Operators record temperature, fallout rate, solution pH, and chamber conditions at regular intervals. Ensure system calibration, cleaning, checking the concentration and pH of the solution used, checking chamber stability, and proper specimen handling.

• The laboratory reports the exposure duration in hours (h) and records the applicable salt spray conditions maintained during the test.
• The analyst records visible changes such as rust formation, corrosion, blistering, or other surface deterioration, as applicable.
• The laboratory documents the location, extent, and appearance of corrosion observed on the exposed specimens according to the specified evaluation criteria.
• A coating that shows less blistering or rust after prolonged fog exposure is considered stronger. Excessive rusting or coating corrosion area denotes a lack of corrosion protection. 
• The report compares the exposed and unexposed specimens and documents the observed corrosion or deterioration.
• The report documents corrosion products by rust grade, blister size, loss of coating adhesion, scribe creep, pitting, delamination, or discoloration, depending on the material class and specification. 

Factors to Consider for ASTM B117

Expert: Skilled personnel are required to maintain a consistent fog environment and interpret corrosion patterns.
Speed: The test provides rapid corrosion screening, though exposure periods may extend from hours to thousands of hours depending on material requirements.
Cost: The cost of the test includes the chamber, salt solution preparation, monitoring equipment, and labor; nevertheless, it is affordable for detecting coating failure at an early stage.

Confidentiality: The laboratory maintains confidentiality throughout the testing process and shares test results only with the relevant stakeholders.

Link to ASTM B117