The Development and Trend of Advanced High Strength Steel Spring
Abstract
Advanced high strength steel spring is an important part of the complete automobile industry chain. Its main function is to improve the safety performance of vehicles, so that vehicles can meet the requirements of safety while achieving light weight, energy saving and environmental protection. This paper first introduces the development process of high strength steel spring, and then focuses on the current status and development trend of advanced high strength steel spring for automobiles, involving metallurgical structure and durability, external surface coating technology and application of alloys performance and other aspects. Finally, conclusion and prospect are given.
1 Introduction
With the development of automobile industry, especially the technical requirements for vehicles in terms of comfort, energy saving and environmental protection, the safety and performance of the vehicle are gradually improved. The high strength steel spring plays an important role in it. Combining the structural characteristics of the spring, the material characteristics of the steel, and the specific requirements of the load, the dynamic performance of the vehicle and the comfort performance are improved. Therefore, the technology of advanced high strength steel spring is particularly important in the development of automobile industry.
2 The development of High-strength steel spring
At present, the high strength steel spring is widely used in the field of automobile manufacturing. The development process of high strength steel spring can be divided into five periods: the infancy period,the initial period,the improvement period,the stability period and the development period .
In the early stage of the automobile industry, the high-strength steel spring was rarely used. Notably, the annual production of automobiles in the world at that time was only 6 million.The manufacturers mainly used the spring of ordinary carbon steel, and the material had low tensile strength, poor fatigue properties and poor corrosion resistance.
In the initial stage of automobile industry development, the high-strength steel spring became increasingly popular with the rapid increase in automobile production and the improvement of the safety performance requirements of vehicles. The initial material selected by the auto manufacturers is the ordinary high-strength spring steel, so that the fatigue performance of the spring still can not meet the requirements. At the same time, with the needs of the industry, automakers began looking for alternatives to spring steel, and in the late 1970s, high-strength steel came out and became the new material for automobile spring.
In the improvement period of high-strength steel spring, automotive manufacturers have improved and developed their high-strength spring steel materials to meet the requirements of safety performance, light weight, energy saving and environmental protection, and achieved good results. High strength spring steel material was used, and the continuously variable spacing of spring coils was adopted. The technology not only improves the fatigue performance of spring, but also reduces the quality of spring and therefore realizes the purpose of light weight of vehicle. Various external surface coating technology have also been developed to further improve the corrosion performance and fatigue performance of spring, so as to improve the applicability of spring material and reduce their maintenance cost.
The development period of high-strength steel spring mainly includes the research on new alloy performance, structure and external surface coating technology. Microalloyed high strength steel spring and maraging high strength steel spring have been developed. With the improvement of the cars dynamic performance, the variable spacing of the film can be used to improve the spring performance and strength of the spring. At the same time, spraying technology, phosphating technology, plastic coating and plasma facility coating technology can significantly improve the external corrosion performance and fatigue performance of high strength spring steel.
3 Current status and Development trend
High strength spring steel has become the main material used by automotive manufacturers in the manufacture of spring due to its good fatigue performance and corrosion performance. The metallurgical structure of high strength steel spring is improved, so as to achieve the purpose of reducing quality and improving dynamic performance. At present, the materials including ultra high strength spring steel, multi-phase high strength spring steel, high durable spring steel and high temperature resistant spring steel have been developed and applied.
At the same time, manufacturers have also been studying a variety of external surface coating technology, which is of great significance to improve the corrosion performance and fatigue performance of high strength steel. The development of external surface coating technology includes zinc plating, electroplating, phosphating, polishing and film coating to meet the needs of the production of automobiles. In addition, different temperature and external environment will also affect the settlement performance, fatigue performance and strength performance of the spring, so in the future, more attention should be paid to the details.
In addition, the rapid development of new energy vehicles has added research topics to high strength spring steel. The main feature of new energy vehicles is the large torque brought by power batteries and motors, so they face higher safety requirements. The high strength spring steel with high strength, toughness, and corrosion resistance is used in many places in the vehicle, such as suspension and suspension parts.
4 Conclusion
High-strength spring steel is the main material for making springs used in automobiles. With the development of materials and manufacturing technology, the performance and quality of high-strength steel have also been improved. Through the introduction of many advanced surface coating technologies, the fatigue performance and corrosion resistance of the spring have been significantly improved, which will play an important role in improving the safety performance of automobiles and realizing high energy saving and environmental protection. In the future, with the further improvement of car performance and the production of new energy vehicles, the research directions of high strength spring steel will also be further widened.
5 Prospect
With the continuous improvement of the performance requirements of vehicles, the development of new materials, new manufacturing and surface treatment technologies will become the main development direction of high strength spring steel. Research on ultra high strength, multi-phase and durable spring steel materials will be carried out, and research on the material structure, heat treatment performance and external surface coating technology of spring steel will also be strengthened. In particular, the corrosion performance and fatigue performance of spring steel will be paid more attention to meet the needs of vehicle performance requirements.
