Benefits of stainless fasteners
| Stainless fastener’s property |
Benefits in comparison to steel/galvanised fasteners |
| Clear surface, exquisite appearance. | Rusty screws give a bad quality impression on the entire end product. |
| Safety | Corrosion reduces the strength and usability of the fasteners. |
| No rust marks | Red rust can, for example, stain plastic parts or textiles. A stainless fastener is easy to clean and, and it is hygienic. |
| No health risks | Cutting oneself with a rusty part can lead to blood poisoning. Galvanised fasteners must be kept separate from contact with food and out of reach of children (licking). |
| Austenitic chrome-nickel steels are almost fully non-magnetic. |
The use of magnetic fasteners, for example in measuring devices, can cause distortions of measurement results. |
| Good heat resistance | At temperatures above 80 ° C, the chrome plating of zinc is destroyed, resulting in significantly reduced corrosion protection. |
| Serviceability | Rusty screws and nuts are difficult to open and require extra work and effort. In order to open the joint, it often has to be broken up, so that there is also a risk of damaging the connected parts. |
Stainless fastener grades
| A2 AISI 304 |
The most common stainless grade in, e.g. chemical industry and household appliances. Stainless, acid-proof and weldable. Not suitable for non-oxidising acids or chlorine-containing conditions, e.g. seawater. Universal screws, sheet metal screws, hex screws, nuts, washers…a wide selection of fastening products. |
| A4 AISI 316 |
The most common acid-proof grade. Resistant to several acids depending on temperature, reasonably resistant to chlorine-containing conditions. Good weldability. Widely used in the wood processing, food and shipbuilding industries. Non-magnetic, non-hardenable. Cold resistance up to -60 °C. Universal screws, sheet metal screws, hex screws, nuts, washers…a wide selection of fastening products. |
| C1 AISI 410 |
Quite good corrosion resistance after surface treatment (e.g. Delta-Magni or corresponding micro-coating). Hardenable grade. Magnetic. Terrace screws, drilling screws, sheet metal screws… generally construction products that need to be hardened. |
The effect of temperature on corrosion: The chemical composition and temperature of the operating conditions have a significant effect on the durability of stainless steel.
Friction factor: The stainless steel surface has a high friction factor (ca. 0.4–0.5). This often requires the use of lubricants when installing or waxing the product.