Irvine Springs is a leading name in bespoke spring manufacturing. For over fifty years, we have advised customers on a global scale about spring design for optimal performance and commercial advantage. A key element of this is ensuring that you have chosen the best spring materials and finishes for your purpose. In this post, we want to help you better understand the different types of springs and their different materials and properties, to feel confident in your design and manufacturing decisions.
The design and manufacturing choices made can have a huge impact on the performance of the spring. The spring materials need to account for the requirements of the finished product, which will affect the overall performance of the spring. Tensile and yield strengths, corrosion resistance, operating temperature and durability, are just some of the factors of which you need to be aware. Consideration of these factors will allow you to make an educated decision on the spring materials you need to create a high quality, reliable end-product.
Spring Materials
The following are seventeen different types of spring materials and their properties, which should be considered when designing your spring. This is intended as a guide only, and an expert should be consulted before manufacture. You can contact a member of the Irvine Springs team for specific advice regarding your needs, and customer care from concept to delivery.
Spring Steel
Spring steel is an all-encompassing term, also known as annealed spring steel. It means that the metal has been heated and allowed to cool slowly. It is one of the most commonly used spring materials, because it is resilient and pliable, with a high yield strength. It is also cheap to produce.
Stainless Steel
Stainless steel has great corrosion and heat resistance, which means the alloy maintains its strength and integrity. There are four kinds of stainless steel, two of which are relevant to the manufacture of springs. Martensitic stainless steel can be hardened through heat treatment, but has reduced chemical resistance. Austenitic stainless steel can be hardened by cold working, which does not impact its chemical resistance.
17/7 PH
17/7 PH is a precipitation-hardening stainless steel. Precipitation-hardening, or PH, is a heat treatment used to increase yield strength. It is strong, with good fatigue and corrosion resistance.
Aluminium
Aluminium is a soft, malleable material that is resistant to corrosion. Since it is not as strong as other metals, it typically needs to undergo specific treatments. Springs made of this material have a wide range of applications, and can be found everywhere from bicycles to aircrafts.
Inconel
Inconel is another material resistant to corrosion. It also retains its strength over a wide temperature range, which is useful for high temperature applications.
Hastelloy
Hastelloy is a kind of superalloy. It is designed to operate under high temperature and stress and highly corrosive or erosive-prone conditions.
Elgiloy/Phynox
Known by both names, Elgiloy is another superalloy. It has high strength and fatigue strength, with high resistance to corrosion and cracking.
MP35N
MP35N has high strength and corrosion resistance. It is an excellent material choice for harsh environments.
Copper
Copper is a good thermal conductor, while being malleable and corrosion resistant. It can be welded, and has good brazing and soldering properties.
Beryllium Copper
Beryllium Copper is high strength and non-magnetic, with good metalworking and machining qualities. However, Beryllium creates an inhalation hazard during manufacturing because it has toxic properties.
Brass
Brass is high strength and flexible. It can also store large amounts of potential and mechanical energy. It is a commonly used material in watches.
Phosphor Bronze
Phosphor Bronze is highly resistant to corrosion, wear and fatigue. It has good tensile strength and is highly ductile. It is an incredibly versatile material with a wide range of applications.
Titanium
Titanium is highly resistant to corrosion, while being both strong and lightweight. It is incredibly versatile, and because of its properties, it is often used in the manufacture of firearms.
Monel
Monel is resistant to corrosion and works well in high temperatures. However, it work-hardens very quickly and so needs to be worked at slow speeds.
Nickel
Nickel demonstrates high levels of corrosion and temperature resistance, with high strength and durability. Several of the materials listed above are actually nickel alloys, which means that they contain multiple elements fused together, and one of these elements is nickel. This includes monel, inconel and hastelloy.
Duplex
Duplex is a kind of stainless steel. It has improved strength and corrosion resistance, and its mechanical properties are double those of austenitic steel.
Super Duplex
Super Duplex is extremely resistant to stress, pitting and crevice corrosion, as well as general corrosion, more so than any other kind of steel. It is composed of 25% chromium, whereas duplex is based around a composition of 22% chromium.
Surface And Plating Finishes
Springs typically require surface and plating finishes to prevent future rusting, and to be more aesthetically pleasing. Different surfaces and plating processes are required depending on the spring material properties. Surface finishing is the process of removing a layer from the material. Plating finishing is the process of adding a layer to the material. In both cases, the aim is the same: improve durability, improve functionality and improve appearance.
Shot Peening
Shot peening is a common surface finishing technique. It strengthens the metal to prevent fatigue stress, while cleaning the surface.
De-embrittlement
De-embrittlement is another surface finishing technique. It is used on metals that have been exposed to hydrogen, because hydrogen makes the material brittle. This process hardens the metal by removing the hydrogen.
Rumbling
Rumbling is a third surface finishing technique. It is used to improve the surface finish, by removing any burrs and sharp edges. It can be used to clean the surface, and remove any rust or dust.
Copper Plating
Copper plating is a common plating finish, often used when a material needs to conduct heat or electricity, and when corrosion resistance is required. It can be used as a base coat for electroplating, and as a decorative finish.
Gold Plating
Gold plating is typically used for aesthetic purposes. It also has electronic applications, as it has good conductivity and wear resistance.
Nickel Plating
Nickel plating is useful because of its solderability, making it a common plating finish within the electronic industry. It is sometimes referred to as an undercoat, as its adhesive properties make it ideal for subsequent coating layers.
Silver Plating
Silver plating is another plating finish commonly used for aesthetic purposes, and within the electronic industry. It has good conductivity and wear resistance.
Tin Plating
Tin plating has good solderability, and is a good electrical conductor. It also withstands corrosion resistance in harsh environments.
Zinc Plating
Zinc plating has incredibly effective anti-corrosive properties. It is commonly used on springs as it ensures maximum resistance.
Summary
Different spring types are best made with different materials and finishes. For example, compression spring materials can include spring steel, stainless steel and beryllium-copper, with as many as ten different materials. Materials for coil springs, such as tension springs, can include spring steel, stainless steel and inconel.
The different spring material properties mean that different finishing processes and surface or plating finishes are required to manufacture the best possible product.
How Can Irvine Springs Help You?
It is evident that there is a huge amount of spring materials and finishes available, and the possibilities and information within this post are not exhaustive. For more detailed information and advice, best practice is to consult a manufacturing expert. The different spring materials properties mean that your choice of material and finish will determine the safety, durability and efficiency of the finished product for which your spring is required.
At Irvine Springs we have a global reputation for engineering excellence, and would be happy to hear any queries or requests you may have – contact us today by calling us on 01294 279396 or emailing us at info@irvinesprings.com.