Both SUS304 stainless steel and SUS400 stainless steel are less likely to rust because an oxide film (passivation film) is formed by the constituent element, chromium. Oxidation film can form even in a normal environment, but corrosion resistance can be improved by using chemicals to form a stronger oxide film. Passivation is a great solution for when you want to improve the corrosion resistance of stainless steel. It is used in precision equipment such as HDD parts, medical equipment, facility devices, and food machinery.
Basic characteristics
| Wear resistance | Heat resistance | Corrosion resistance | Chemical resistance | Decorativeness | Lubricity | Adhesion | Electrical conductivity | Dimensional accuracy |
| - | - | ◎ | ◎ | - | - | - | - | ◎ |
Features
Features 1It is a process to form an oxide film on the stainless steel surface (passivation treatment). The details of the processing method are specified by such standards as the American MIL standard and the ASTM standard. Nitric acid-based materials are generally used for SUS300-based materials, and nitric acid-chromic acid-based solutions are generally used for SUS400-based materials. Our passivation supports two types of nitric acid-based liquids: Type-VI and Type-VIII. We can perform laboratory testing for nitric acid-chromic acid passivation. Please contact us for more information. Quoted from QQ-P-35 Type VI. Type VI solution shall contain 25-45 percent by volume of nitric acid (HN03) in accordance with O-N-350. Parts shall be processed for 30 minutes at a temperature range between 70-90°F (21-32°C). Type VI solution can be used to process austenitic 200 and 300 series chromium nickel and chromium grades with 17% chromium or greater (with exception of the 440 series) corrosion-resistant steels. 3.3.8 Type VIII. Type VIII solution shall contain 45-55 percent by volume of nitric acid in accordance with O-N-350. Parts shall be processed for 30 minutes at a temperature range between 120-130°F (49-54°C). Type VIII solution can be used for parts made from high carbon and high chromium grades (400 series) and precipitation-hardening stainless steels.
Features 2This treatment does not produce a metal film so no dimensional changes occur. Passivation can improve the corrosion resistance of the oxide film while maintaining the dimensions.
Plating equipment
| Processing type | Maximum size | Maximum weight |
| Basket | Basket | 2kg |
Proceccable materials
SUS300 series, SUS400 series *
*We may not be able to support SUS400 series. Please contact us for more details.
Application
Precision equipment parts, sensors, automobile parts, machinery parts, etc.