Application and Practice of LISUN Cyclic Corrosion Chamber in Material Corrosion Performance Evaluation

Abstract
Salt spray corrosion is a major cause of material failure in marine environments, automotive industries, and industrial production fields. Accurately evaluating the salt spray resistance of materials and coatings is crucial for ensuring product durability and reliability. This paper takes the LISUN YWX/Q-010 Cyclic Corrosion Chamber as the research object, systematically expounding its working principle, technical specifications, applicable standards, and application scenarios. By analyzing the specific operating procedures and data performance of this equipment in the testing of metal materials, electronic components, and industrial product protective layers, its accuracy and stability in simulating corrosive conditions in harsh environments are verified. The research shows that the LISUN YWX/Q-010 Cyclic Corrosion Chamber can accurately reproduce the salt spray corrosion process through various test modes such as Neutral Salt Spray (NSS), Acetic Acid Salt Spray (AASS), and Copper – Accelerated Acetic Acid Salt Spray (CASS). It provides a scientific basis for material selection, coating quality control, and product life prediction, and has important practical value for improving the service performance of industrial products in harsh environments.

1. Introduction
In industrial production and product application, harsh conditions such as high salinity in marine environments, road salt erosion on automotive chassis, and corrosive gases in industrial workshops easily cause corrosion failure of metal materials and product protective layers, leading to structural damage, functional failures, and even safety accidents. According to industrial corrosion data statistics, the annual economic loss caused by metal corrosion worldwide accounts for 3% – 5% of GDP, among which salt spray corrosion accounts for more than 60% of atmospheric corrosion failure cases. Therefore, using professional equipment to simulate the salt spray environment and evaluate the corrosion resistance of materials and coatings in advance has become a core link in industrial product design, production, and quality control.

As a special equipment for simulating the salt spray corrosion environment, the cyclic corrosion chamber accelerates the corrosion process of materials by artificially creating saltwater mist. It can obtain the corrosion resistance data of materials in a short time, greatly shortening the test cycle in the natural environment. As a professional brand in the field of environmental test equipment, LISUN has developed the YWX/Q-010 Cyclic Corrosion Chamber, which is widely used in electronics, automotive, aerospace, hardware, and other industries due to its compliance with multiple international and domestic standards, stable technical parameters, and convenient operation. This paper focuses on the technical characteristics and application practice of this equipment, aiming to provide reference for corrosion testing work in related industries.

2. Principle of Salt Spray Corrosion and Working Mechanism of Cyclic Corrosion Chamber
2.1 Principle of Salt Spray Corrosion
Salt spray corrosion is a typical electrochemical corrosion process, and its core medium is saltwater mist containing chloride ions (Cl⁻). When the salt spray comes into contact with the surface of metal materials, it forms a conductive electrolyte film, which destroys the oxide passivation layer on the metal surface:

1. Penetration of Chloride Ions: Cl⁻ has a small ionic radius and strong adsorption capacity. It can penetrate the oxide layer or coating pores on the metal surface, undergo an electrochemical reaction with the internal metal, and generate soluble chlorides (such as FeCl₂, AlCl₃), leading to the failure of the passivation layer;
2. Acceleration of Electrochemical Reaction: The formation of the electrolyte film forms anodic and cathodic regions on the metal surface. Metal dissolution occurs at the anode (e.g., Fe – 2e⁻ = Fe²⁺), and oxygen reduction occurs at the cathode (O₂ + 2H₂O + 4e⁻ = 4OH⁻). Finally, corrosion products such as ferrous hydroxide are generated, further aggravating material damage;
3. Synergistic Effect of Humidity and Temperature: A high – temperature and high – humidity environment can improve the conductivity of the electrolyte film, accelerate ion migration, and increase the corrosion reaction rate by 3 – 5 times. This is the key reason why the cyclic corrosion chamber needs to accurately control temperature and humidity.

2.2 Working Mechanism of LISUN YWX/Q-010 Cyclic Corrosion Chamber
The LISUN YWX/Q-010 Cyclic Corrosion Chamber realizes the simulation of the salt spray corrosion environment through a closed – loop process of “saltwater preparation – atomization – temperature control – sedimentation collection – corrosion observation”. The specific working mechanism is as follows:

1. Saltwater Preparation and Storage: The equipment is equipped with a 32L saltwater tank. Saltwater of different concentrations can be prepared according to test standards (e.g., a 5% sodium chloride solution with a pH value of 6.5 – 7.2 is required for the NSS test). The saltwater enters the atomization system after filtration;
2. Compressed Air Treatment: An external air compressor (it is recommended to select the LISUN LS – EU800W2 – 55L air compressor) provides compressed air with a pressure of more than 0.4MPa. The compressed air is heated to 60 – 70℃ in a saturation barrel (to match the test temperature and avoid a sharp drop in temperature after atomization). At the same time, moisture and impurities are removed to ensure the atomization quality;
3. Atomization and Sedimentation: The treated compressed air atomizes the saltwater into droplets of 5 – 10μm through a nozzle, which are evenly sprayed into the working chamber (1200800500mm). The equipment stabilizes the temperature of the working chamber at 35℃ (for the NSS test) or 50℃ (for the AASS/CASS test) through a temperature control system, ensuring that the salt spray sedimentation rate is controlled at 1 – 2ml/80cm²·h (16 – hour average value);
4. Test Monitoring and Termination: During the test, the equipment monitors the operating status in real – time through low – water level alarm and over – temperature alarm (mechanical + electronic dual protection). After the test is completed, the samples are taken out to observe the corrosion degree (such as rust area, coating peeling), and rated according to the standards.

3. Application Practice of LISUN YWX/Q-010 Cyclic Corrosion Chamber
Taking the “salt spray resistance test of galvanized steel chassis brackets” in the automotive industry as an example, this paper elaborates on the operation process, data recording, and result analysis of the LISUN YWX/Q-010 Cyclic Corrosion Chamber, and verifies its application value.
3.1 Test Preparation
1. Sample Preparation: Select 3 galvanized steel chassis brackets of the same specification (size 30020050mm), wipe the surface with alcohol to remove oil stains, and mark them as Sample 1, Sample 2, and Sample 3;
2. Saltwater Preparation: According to the GB/T 10125 – 2012 standard, weigh 250g of sodium chloride (analytical pure), dissolve it in 5L of deionized water, stir evenly, and adjust the pH value to 6.8 with hydrochloric acid or sodium hydroxide to prepare a 5% neutral salt spray test solution;
3. Equipment Debugging:
• Inject the prepared saltwater into the saltwater tank of the LISUN YWX/Q-010 Cyclic Corrosion Chamber until it reaches the water level line;
• Turn on the equipment power, set the test temperature to 35℃, the saturation barrel temperature to 65℃, the spray mode to continuous spray, and the test duration to 48 hours;
• Install the samples: Fix the 3 samples on the sample rack (the angle of the sample rack is adjusted to 20°±5°, in line with the standard requirements), ensuring that the sample surface is not blocked and the salt spray can cover it evenly;
• Check the equipment status: Turn on the air compressor, adjust the spray pressure to 0.12MPa, observe the salt spray sedimentation, and start the test after the temperature of the working chamber is stabilized at 35℃±0.5℃.

3.2 Test Process Monitoring
During the test, the following data are recorded through the real – time monitoring system of the LISUN YWX/Q-010 Cyclic Corrosion Chamber:

Monitoring Items	Set Value	12 – hour Measured Value	24 – hour Measured Value	36 – hour Measured Value	48 – hour Measured Value
Working Chamber Temperature (℃)	35±0.5	34.8	35.1	34.9	35
Saturation Barrel Temperature (℃)	65±1	64.7	65.2	64.9	65.1
Salt Spray Sedimentation Rate (ml/80cm²·h)	1-2	1.5	1.6	1.4	1.5
Spray Pressure (MPa)	0.12±0.02	0.118	0.121	0.119	0.12

It can be seen from the monitoring data that during the entire test process, the temperature fluctuation of the LISUN YWX/Q-010 Cyclic Corrosion Chamber is ≤±0.5℃, the salt spray sedimentation rate is stable at 1.4 – 1.6ml/80cm²·h, and the spray pressure fluctuation is small, which meets the standard requirements. This indicates that the equipment operates stably and the test conditions are controllable.

Tags：YWX/Q-015