Deciding on a material is a crucial step in spring design. This article focuses on copper, brass, and bronze. These metals each have their own set of advantages and disadvantages that have to be studied, especially in terms of corrosion resistance, conductivity, cost, and strength. For example, consider designing springs for a location near the sea where there is salt water. Brass is a good option due to its high resistance to corrosion. However, if your budget is tight, copper might be a better choice despite its weaker corrosion resistance. This article aims to help engineers understand these metals in order to make informed decisions in their design process.

Advantage - Corrosive Environments

Copper, brass, and bronze springs are resistant to rust, which is advantageous in environments where corrosion is likely. This is due to the protective layer these metals form when exposed to air and water. This property is of benefit in corrosion-prone environments, specifically in the maritime and chemical sectors. In the marine industry, where there is regular exposure to saltwater, metal components such as springs can rust and degrade rapidly. In such circumstances, springs made of steel deteriorate quicker than those made of copper, brass, or bronze, leading to higher maintenance costs.

However, it's important to note that despite the corrosion resistance of copper, brass, and bronze springs, they might not have the same strength as steel springs. In settings where high tensile strength is required, these springs might not perform as well as their steel counterparts. Therefore, it's recommended to select springs based on the strength required and the exposure conditions. In a situation where a balance of moderate strength and good corrosion resistance is needed, bronze springs can be a suitable choice.

The corrosion resistance property of copper, brass, and bronze springs, along with their ability to operate in different environmental conditions, can make these springs more durable under certain conditions. This can increase their service life, which in turn can decrease the frequency of replacement and the costs associated with it. This can potentially assist in managing the lifecycle costs of equipment and mechanisms that use these springs.

Advantage - Conductivity

Copper, brass, and bronze springs have electrical and thermal conductivity properties. Of these, copper springs exhibit the highest levels of both electrical and thermal conductivity. In a real-world application such as a thermostat, a copper spring could enable or prevent electrical current flow, affecting the operation of the thermostat and the temperature of the system. This shows how the level of thermal conductivity of a spring can influence an application. Brass and bronze springs can perform similarly, yet they offer less conductivity than copper. This difference could alter the device's behavior.

However, high conductivity might not always be desired. For example, if an application requires the spring to reduce the transmission of electrical current or heat, then choosing copper, brass, or bronze may not be suitable. Thus, during spring design, engineers should take into account the conductivity properties of the material in accordance with the needs of their specific application.

Disadvantage - Cost

Copper, brass, and bronze springs have a higher cost compared to other materials such as steel or iron. This rise in cost is distinctly noticeable when these expensive metals are used in large-scale production, leading to higher manufacturing costs and a potentially increased final product price.

An observable example of this exists in the automotive industry. In a situation where a car manufacturer chooses brass springs for the vehicles' suspension systems over the more affordable steel options, the cumulative cost, due to the large number of springs required in each vehicle, can contribute to an increase in the vehicle's final price.

However, the cost is not an absolute deterrent to the use of copper, brass, or bronze springs. These materials offer qualities such as improved resistance to corrosion and visual appeal, which can counterbalance their higher expense in specific situations. Therefore, when selecting the materials for spring design, engineers and designers must consider both the benefits and costs of these metals. An assessment of project demands, budget, and feasible trade-offs is an integral step of this process.

Disadvantage - Strength

Copper, brass, and bronze differ from materials such as high carbon steel or stainless steel because they prioritize conductivity over load-bearing strength. These metals offer less strength, which may restrict their applicability in certain high-stress scenarios.

The production of vehicle springs, for instance, often necessitates a high-stress environment. If copper, brass, or bronze are used in these situations, it could result in deformation under significant load. However, this constraint does not exclude these materials from being used in the fabrication of springs entirely, it merely suggests their use towards specific applications.

In environments with low-stress levels that require corrosion resistance, the properties of copper, brass, and bronze are advantageous. These metals are particularly suited to maritime equipment or outdoor installations. Here, exposure to saltwater and harsh weather elements is common. While these materials may not be as strong as stainless or high carbon steel, there is a reduced demand for high load-bearing capacity in these settings, making them a suitable choice.


In summary, copper, brass, and bronze springs have distinctive benefits and shortcomings. The corrosion resistance and conductivity of these metals suit certain uses but may not be cost-effective or meet strength requirements for some projects. Therefore, aligning the needs of the project with the characteristics of these materials is crucial in selecting the appropriate spring type. For instance, if the project calls for conductive springs and has a flexible budget, copper springs might fulfill those needs. Conversely, if the project requires springs that are reasonably priced with acceptable strength and corrosion resistance, then brass or bronze springs could be the best options. Remember that the primary goal is to match the spring design and material to the unique requirements of the project.