Corrosion resistance test of metal electrophoretic connectors: technical analysis and application cases of salt spray test chamber

I. The core role of the salt spray test chamber and test principle

Salt spray test chamber is the key equipment for assessing the corrosion resistance of metal electrophoresis connectors, accelerating the corrosion process by artificially simulating a high concentration of salt spray environment, significantly reducing the test cycle. The test is divided into two categories:

Natural environmental exposure test: relies on actual environmental conditions, with a long and uncontrollable cycle.

Artificial simulation of salt spray test: based on the salt spray test chamber to accurately control the chloride concentration, temperature and humidity and other parameters, can be simulated within a few hours months or even years of corrosion effects.

II. The salt spray test chamber test mode and parameter settings

Test mode

NSS (Neutral Salt Spray): pH 6.5~7.2, applicable to conventional metal parts.

ASS (Acidic Salt Spray): pH 3.1~3.3, simulating industrial pollution environment.

CASS (Copper Accelerated Salt Spray): add trace copper chloride, corrosion rate increased by more than 50%.

Core parameters (TEMAK standard salt spray test chamber as an example)

Temperature range: 35 ℃ ~ 55 ℃ (can be precisely adjusted ± 0.5 ℃).

Humidity range: 85%~100% RH (humidity sensor precision ±3%).

Spray mode: continuous or intermittent alternating (support customized program)

Falling mist volume: 1-2ml/80cm²-hr (adjustable range 1-3ml/80cm²-hr), uniformity ±0.3ml.

Sample angle: 20°±5°tilt to ensure uniform coverage of salt spray.

III. The salt spray test chamber in the metal electrophoresis connectors test in the actual application

Case background: a batch of metal electrophoresis connectors need to verify its corrosion resistance in coastal high salt environment.

Test conditions

Environmental temperature and humidity: laboratory temperature 19 ℃ ~ 21 ℃, humidity 41% RH ~ 43% RH.

Equipment selection: Salt spray test chamber to perform NSS test, parameters set according to Table 1.

Test process

Pre-treatment: Check the appearance of the front and back of the sample before the test, and record the surface condition.

Test execution: Salt spray test chamber continuous spraying for 48 hours, falling mist volume 1.5ml/80cm²-hr, temperature constant 35℃.

Appearance of the sample before testing: 

front

Appearance of the sample before testing: reverse 

side

Judgment of results: no abnormal appearance of the sample after the test (no judgment at the drilling hole), no blistering, peeling or rusting.

IV. The technical advantages of salt spray test chamber and industry value

Accelerated testing capability

The salt spray test chamber can compress the natural corrosion cycle to 1/10, for example, 48 hours of testing is equivalent to 6 months of exposure to coastal environments.

Data Reproducibility

The constant temperature and humidity system and high-precision spray control of the salt spray tester ensures comparable results across batches.

Quality Control Basis

After the metal electrophoresis connectors are verified by the salt spray test chamber, it can be clear whether the coating thickness, denseness and other processes are up to the standard, which can provide the basis for the improvement of the electrophoresis parameters (e.g. voltage and time).

V. Salt spray test standard and equipment selection suggestions

Mainstream standard reference

ISO 9227: Standardize the neutral, acidic and copper accelerated salt spray test method.

ASTM B117: Requirements for salt spray test chamber falling mist uniformity error ≤ ± 0.5ml/80cm²-hr.

Points for equipment selection

Select the salt spray test chamber that supports NSS/ASS/CASS modes to meet the needs of multi-scenario testing.

Ensure that the box material is corrosion-resistant PVC or fiberglass, to prevent long-term salt spray erosion of the equipment structure.