Can stainless fasteners be used with aluminium?

This is one of the most common questions we receive.

If you look online, you’ll find a lot of mixed information about using stainless steel fasteners with aluminium. The concern is usually around galvanic corrosion, which can occur when dissimilar metals are in contact in the presence of moisture or saltwater.

In Australia, aluminium bolts, nuts, and screws are very difficult to source in a wide range of sizes and styles. While some overseas suppliers offer them, pricing and availability can make them impractical. Because of this, stainless fasteners are widely used with aluminium across many industries.

A good example is marine applications, where boats are commonly assembled using stainless fasteners. Aluminium window frames are also often secured with stainless self-tapping screws.

In many general-purpose and dry applications, stainless steel and aluminium are used together successfully every day. The risk of corrosion is typically higher in wet, coastal, or saltwater environments.

If corrosion is a concern, there are several ways to reduce the risk:

• Use nylon washers to separate the materials
• Paint or coat one of the surfaces
• Apply a protective product such as Tef-Gel or Duralac
• Avoid trapping moisture between the materials

These prevention methods are commonly used in marine and architectural applications where stainless fasteners and aluminium are used together.