Electrolytic polishing corrosion tester is a precision equipment based on electrochemical principles, which achieves surface leveling and microstructure exposure through electrochemical reactions between electrolyte and metal samples. The core principle can be summarized as the thin film theory: when a metal sample is immersed in an electrolyte as an anode, the surface protrusions have a thinner viscous film, lower resistance, higher current density, faster dissolution rate than the depressions, and ultimately form a smooth surface. This process avoids the deformation layer generated by mechanical polishing and can truly reflect the material's organizational structure.
The core functions of the device are divided into two modules:
Electrolytic polishing: precise control of current density through constant current/constant voltage mode, removing metal surface oxide films, scratches, and small protrusions. For example, stainless steel samples can achieve mirror effect and significantly reduce roughness in 30-120 seconds at a voltage of 15-30V and a current density of 0.1-2A/cm ². The device supports voltage regulation within the range of 0-100V and current regulation within the range of 0-20A, and is compatible with non-ferrous metals such as titanium, aluminum, copper, and high-temperature alloys.
Electrolytic corrosion: Selective dissolution of grain boundaries or phase boundaries by adjusting the electrolyte composition, revealing the microstructure. For example, after being treated with a specific electrolyte, the grain morphology and precipitation phase distribution of nickel based alloys can be clearly observed. Some models are equipped with mixing devices and water cooling systems to ensure uniform flow of corrosive media and avoid tissue distortion caused by local overheating.
The equipment has significant advantages: the sample preparation efficiency is improved by more than 50% compared to mechanical polishing, and the repeatability error is less than 5%; The CNC model supports computer data input and polarization curve analysis, and can store 200 sets of process parameters; Safety protection includes leakage protection, automatic power-off due to overheating, and anti-corrosion shell design. In the aerospace field, this equipment is used for metallographic testing of turbine blades; In the medical device industry, titanium alloy implant samples without deformation layers can be prepared to provide critical support for material research and quality control.