Abstract
This article provides a detailed introduction to Inconel 718 canted coil springs, covering their material properties, structural characteristics, performance advantages, application fields, and manufacturing processes. These springs, leveraging the high strength, excellent corrosion resistance, good oxidation resistance, and thermal stability of Inconel 718, combined with unique structures such as canted coils, possess properties like high elasticity, good fatigue resistance, and low friction and wear. They are widely used in aerospace, petrochemical, energy and power, and other fields. Additionally, the key links in their manufacturing process are elaborated.
In the industrial sector, many equipment and systems need to operate stably in extreme environments, which places extremely high demands on their components. As an important elastic element, springs play a crucial role in shock absorption, buffering, energy storage, etc. However, ordinary springs often fail to meet the requirements in harsh conditions such as high temperature, high pressure, and strong corrosion. Inconel 718 canted coil springs are high-performance components developed to cope with such severe working conditions. They combine high-quality Inconel 718 material with a unique canted coil structure, demonstrating excellent performance.
Material Properties
- High Strength: After solution treatment and aging strengthening, Inconel 718 has extremely high strength. Its yield strength is usually above 1000MPa, and its tensile strength can reach 1300MPa or even higher, enabling it to bear large loads and be suitable for occasions with high strength requirements.
- Excellent Corrosion Resistance: The alloy contains a large amount of nickel, chromium, molybdenum, and other elements, making it perform well in various corrosive environments. It has strong corrosion resistance in chloride solutions, sulfuric acid, phosphoric acid, and other corrosive media, and can effectively resist pitting, crevice corrosion, stress corrosion cracking, and other forms of corrosion.
- Good Oxidation Resistance: In high-temperature environments, a dense oxide film forms on the surface of Inconel 718. This oxide film can prevent oxygen from further reacting with the alloy matrix, thus exhibiting good oxidation resistance and can work stably for a long time in high-temperature oxidizing atmospheres.
- Thermal Stability: It has a low coefficient of thermal expansion. In environments with large temperature changes, Inconel 718 canted coil springs can maintain good dimensional stability, reducing performance changes caused by thermal expansion and contraction. At the same time, it still maintains good mechanical properties at high temperatures, with high creep strength and rupture strength, and can bear loads for a long time at high temperatures without obvious deformation and failure.
Structural Characteristics
- Canted Coil Structure: The coils of Inconel 718 canted coil springs are canted at a certain angle with the axis. This unique structure allows the force to be more evenly distributed on each coil when the spring is loaded. Compared with traditional straight coil springs, the stress concentration phenomenon is significantly improved, thereby enhancing the bearing capacity and service life of the spring.
- Variable Helix Angle: The helix angle of canted coil springs can be designed and adjusted according to specific application requirements. By changing the size of the helix angle, performance parameters such as the stiffness, elastic deformation capacity, and bearing capacity of the spring can be altered to adapt to different working conditions and load requirements.
- Compact Structural Design: Due to the canted coils of the canted coil spring, more coil turns can be accommodated under the same outer diameter and height dimensions, thereby increasing the elastic deformation and energy storage capacity of the spring, achieving a compact structural design, which has obvious advantages in some space-constrained occasions.
- High Elasticity and Energy Absorption Capacity: Inconel 718 canted coil springs have a high elastic modulus and good elastic deformation capacity. They can undergo large elastic deformation when bearing loads and convert the work done by external forces into elastic potential energy for storage. After unloading, the spring can quickly return to its original shape and release the stored elastic potential energy, realizing the function of energy absorption and release, and can be used in shock absorption, buffering, energy recovery, and other fields.
- Good Fatigue Resistance: Inconel 718 itself has excellent fatigue resistance. Coupled with the reasonable structural design of the canted coil spring, the spring has a long fatigue life under cyclic loads of repeated loading and unloading. After millions or even tens of millions of cyclic loadings, it can still maintain good performance, is not prone to fatigue fracture and other failure forms, and improves the reliability and stability of the equipment.
- Low Friction and Wear Characteristics: During the operation of the canted coil spring, the relative movement between the coils is small, and the friction and wear are correspondingly reduced. At the same time, Inconel 718 has good wear resistance, which further reduces the wear degree of the spring during use, reduces the risk of performance degradation and failure of the spring caused by wear, prolongs the service life of the spring, and reduces maintenance costs.
Application Fields
- Aerospace Field: Used in parts such as the fuel injection system of aircraft engines, the shock absorption device of landing gear, and the actuator of flight control systems. It can work reliably in extreme environments such as high temperature, high pressure, and high vibration, ensuring the safe flight and stable performance of the aircraft.
- Petrochemical Industry: In the process of oil extraction, refining, and chemical production, Inconel 718 canted coil springs can be applied to various pumps, valves, pipeline connections, and other equipment for sealing, shock absorption, compensation for thermal expansion, etc. They can resist the corrosion of petroleum and chemical media and the effects of high temperature and high pressure, ensuring the long-term stable operation of the equipment.
- Energy and Power Field: In energy facilities such as nuclear power plants, thermal power plants, and wind power plants, Inconel 718 canted coil springs can be used in components of steam turbines, generators, boilers, etc., such as for supporting, shock absorption, sealing, and other functions. They can maintain good performance in harsh environments such as high temperature, high humidity, and high radiation, ensuring the normal operation of energy equipment and the stable supply of electricity.
Manufacturing Process
- Raw Material Preparation: High-quality Inconel 718 bars, wires, or plates are selected as raw materials. The raw materials are strictly inspected and tested to ensure that their chemical composition and mechanical properties meet the requirements.
- Forming Processing: Advanced processing technologies such as CNC winding, cold forming, or hot forming are used to process the raw materials into the shape of canted coil springs. During the forming process, it is necessary to accurately control processing parameters such as coil diameter, pitch, and helix angle to ensure the dimensional accuracy and shape accuracy of the spring.
- Heat Treatment: The formed canted coil springs undergo solution treatment and aging strengthening treatment to improve their strength, hardness, and fatigue resistance. Solution treatment can eliminate internal stress in the spring and make the alloying elements fully dissolve in the matrix; aging strengthening treatment can further improve the mechanical properties of the spring by precipitating fine strengthening phases.
Inconel 718 canted coil springs play an irreplaceable role in many fields with strict requirements on components due to their excellent material properties, unique structural design, and outstanding performance. With the continuous development of industrial technology, the demand for such high-performance springs will continue to increase, and their manufacturing processes will also be continuously optimized and improved. It is expected to be applied in a wider range of fields in the future, providing more reliable guarantees for the stable operation of industrial equipment.
