Many find, when choosing anti-rust products, there are both anti-rust agents and anti-rust oils. Initially, it was thought these were just two names for the same thing. However, it was later discovered that, although both have anti-rust properties and share similar chemical compositions, their effects differ. So, when selecting anti-rust products, should one choose an anti-rust agent or anti-rust oil?

Let's first understand the working principles of these two anti-rust products. Both rust inhibitors and anti-rust oils form a strong adsorptive film on the surface of metals, thereby inhibiting contact between oxygen and water, particularly water, with the metal surface. This prevents the metal from coming into contact with air and water, which leads to rust. The lubricating anti-rust agents are mainly used in industrial lubricants, metal processing cooling and lubricating fluids, and metal protective oils.

The Difference Between Rust Inhibitors and Rust Oils:

Corrosion Inhibitor, a water-based product also known as corrosion fluid, is formulated with additives that provide corrosion protection. Its advantages include ease of use, affordability, and easy cleaning. The duration of the corrosion protection offered by the inhibitor varies depending on the usage ratio, ranging from one month to a year. The less water used, the better the corrosion protection.

Antirust oils formulated from additives must have sufficient adsorption to metals and solubility in oil, thus they are composed of strong polar groups and appropriate hydrophobic groups. Currently, the widely used and effective types include sulfonates (calcium sulfonate, sodium sulfonate, and barium sulfonate), carboxylic acids and their salts (dodecenyl succinic acid, zinc naphthenate, N-octadecyl sarcosinate), organic phosphates such as imidazoline salts, ester-type antirust agents (lanolin and lanolin soap with benzyl-60 or 80, petroleum oxide), heterocyclic compounds (benzotriazole), and organic amines, etc. Water-soluble antirust oils mainly include sodium nitrite, potassium dichromate, sodium tripolyphosphate, diammonium hydrogen phosphate, sodium benzoate, triethanolamine, etc.

Compared to rust preventives, rust oils offer a longer-lasting rust prevention, are more expensive, and provide superior rust protection. Even when using transparent quick-dry film rust oil, there will still be an oiliness sensation on the surface.

The anti-rust oil has the following two characteristics:

A certain degree of viscosity or thickness, when applied to metal surfaces, forms a hard or soft, continuous film that isolates from air and water, preventing rust on ferrous or non-ferrous metals.

All types of rust-proof oils are of long-lasting anti-rust properties, with a protection period of about five years. However, when reusing the machinery, the anti-rust film can be easily washed off with kerosene or degreaser at any time, distinguishing it from anti-rust paint used for the same purpose.

Choosing Methods for Rust Preventive Oils and Agents

If the requirement for rust prevention time is short, rust inhibitors can be used. Similarly, if the workpiece needs to be easily cleaned after use, rust inhibitors are also a suitable choice. Conversely, for longer-lasting protection, rust oil should be selected.