MIL-STD-810H Salt Fog (Method 509.7) Test Machine.

MIL-STD-810H (Method 509.7) Salt Fog

MIL-STD-810G (Method 509.5) Test Machine

The MIL-STD-810H (Method 509.7) Salt Fog Test Machine is designed to evaluate the durability of devices in corrosive salt environments. This machine is essential for testing the long-term reliability and durability of equipment used in marine, military, and industrial applications, where exposure to salt conditions can cause corrosion.

Test Objectives

• Corrosion Resistance: Measures the resistance of materials and coatings to corrosion caused by salt environments.
• Performance Degradation: Tests the performance loss in electronic and mechanical components due to salt fog exposure.
• Accelerated Aging: Simulates long-term exposure to salty environments for accelerated product durability testing.

1. Scope

This method evaluates the resistance of materials and protective coatings to salt-laden environments, particularly for equipment exposed to marine or high-salinity conditions.

• Purpose: To determine the effectiveness of protective coatings and finishes on materials, and assess the impact of salt deposits on their physical and electrical properties.
• Application: This test is primarily used for screening purposes, ensuring the durability of protective coatings, identifying quality control issues, and detecting design flaws in a short time.
• Limitations:
  • The test does not replicate real-world exposure durations or the complex chemical composition of marine environments.
  • It does not establish a direct correlation between salt fog exposure and corrosion caused by other media.
  • Passing this test does not guarantee resistance to all corrosive conditions.

2. Tailoring Guidance

This section explains how to adapt the test method to specific requirements.

• Effects of Corrosive Environments:
  • Corrosion Effects: Electrochemical corrosion, accelerated stress corrosion, and formation of acidic/alkaline solutions.
  • Electrical Effects: Salt deposits can impair electrical performance, create conductive coatings, and corrode insulation.
  • Physical Effects: Clogging or binding of mechanical components, paint blistering due to electrolysis.
• Test Sequence Considerations:
  • If the same test sample is used for multiple tests, thorough cleaning is required after salt fog exposure.
  • Salt fog testing is generally conducted after other environmental tests, such as humidity and fungus exposure.

3. Information Required

Before, during, and after testing, specific data must be collected.

• Pre-Test: The condition of the test sample, coating specifications, and sensor calibration should be documented.
• During Test: Chamber temperature, humidity, salt solution concentration, fallout rate, and pH must be recorded.
• Post-Test: Observations of corrosion, electrical failures, and mechanical deterioration are analyzed.

4. Test Process

This section details the experimental setup and procedure.

• Test Facility Requirements:
  • The test chamber must maintain controlled humidity, temperature, and salt fog conditions.
  • The salt solution should be composed of 5 ±1% NaCl.
  • The chamber should allow consistent salt fog fallout between 1-3 ml per 80 cm² per hour.
• Test Setup & Execution:
  • The sample is placed in the chamber at 35 ±2°C (95 ±3.6°F) for at least two hours before testing.
  • The salt fog is continuously atomized into the chamber for 24 hours or per the test plan.
  • The test item is then dried under controlled conditions for another 24 hours before repeating the cycle.
• Test Duration:
  • A minimum of four 24-hour cycles (two wet and two dry) is recommended.
  • Alternative test durations include 48 hours of continuous salt fog exposure followed by 48 hours of drying.

5. Analysis of Results

• The test results are analyzed for corrosion impact, electrical failures, and mechanical degradation.
• Any deviations from expected results are documented.
• Additional tests may be necessary for long-term durability assessments.

6. Reference Documents

• ASTM B117: Standard Practice for Salt Fog Testing.
• MIL-HDBK-310: Global Climatic Data.
• NATO STANAG 4370: Environmental Testing Standards.

Summary of MIL-STD-810H Method 509.7 – Salt Fog Test

The Salt Fog Test in MIL-STD-810H evaluates the resistance of equipment to marine and high-salinity environments.

Test Process:

• Salt Fog Exposure: A continuous 24-hour salt fog exposure followed by a 24-hour drying cycle, repeated for at least four cycles.
• Corrosion & Electrical Impact Assessment: The effects of salt deposits on materials and electronic components are analyzed.

Effects Evaluated:

• Corrosion of metals and protective coatings
• Electrical malfunctions due to salt deposits
• Mechanical degradation, including clogging and paint blistering

Final Assessment:

• The test data helps predict equipment durability in salt-laden environments.
• This test is crucial for military, industrial, and marine applications where exposure to salt fog is a concern.

Key Features

Feature Value / Description Salt Solution Ratio 5% NaCl solution (standard) Temperature Range 25°C – 55°C (programmable) Spray Rate 1 – 2 ml/80 cm²/hour (complies with MIL-STD-810H requirements) Cabinet Volume 100 L – 2000 L (available in various sizes) Humidity Control 30% – 98% relative humidity Test Duration 1 hour – 1000 hours (customizable test cycles) Control System Fully automated PLC-based control, user-friendly touch screen Material Stainless steel or corrosion-resistant polymer Power Requirements 220V AC, 50 Hz or 380V AC, 50 Hz Monitoring and Logging Real-time recording of test parameters, LAN/USB support Optional Features Automatic salt solution preparation system, camera-based test monitoring

Application Areas

• Maritime: Testing the durability of ship equipment and marine vehicles in saltwater conditions.
• Military: Environmental reliability of devices used in coastal and maritime regions.
• Automotive and Electronics: Assessing the corrosion resistance of automotive parts, electronic devices, and coated surfaces.

For more detailed information about the MIL-STD-810H (Method 509.7) Salt Fog Test Machine and to place an order, please contact us!

Standard reference

MIL-STD-810H Method 509.7 defines the Salt Fog test. The item is exposed to alternating salt-fog and drying periods (commonly 24-hour cycles) to reveal corrosion, electrical effects and the blocking of moving parts. The salt-solution concentration, number of cycles and exposure/drying durations follow the standard.