In the manufacturing field, rust on Screws is a serious issue. Rust on screws poses a significant challenge, as it directly affects product quality and safety. However, by understanding the root causes and taking appropriate preventive measures, you can enhance product reliability and prevent unexpected problems. This article explains the main causes of screw rust, practical prevention methods you can apply on-site, and techniques for removing screws that have already seized due to rust—all practical know-how that engineers can put to use immediately.

3 Main Causes of Screw Rust

Rust is caused by oxidation, where metal reacts with oxygen and moisture in the air. The following three conditions accelerate the process:

1: Moisture and Water Exposure
High-humidity environments (above approx. 65%) or water droplets on screws increase the likelihood of rust. This applies not only outdoors, but also in garages on rainy days or inside toolboxes that are not properly sealed. Oxygen dissolved in water reacts with iron to form familiar red rust. •: In coastal environments, salt absorbs moisture from the air, keeping screw surfaces damp and accelerating rust. •: When metals with different potentials (e.g., iron and aluminum) come into contact, corrosion occurs. This is known as dissimilar metal corrosion or galvanic corrosion. Exhaust gases containing sulfur, chlorides, dust, dirt, or chlorine-based cleaners can all accelerate rusting. Maintaining a clean working environment is therefore essential.