Development and Application of Advanced Delay-Fracture High Strength Bolt Steel
High strength bolt steels are widely used in various industrial fields, such as automotive and bridge construction, because of their high strength, resistance to corrosion and fatigue, and good weldability. However, due to the nature of steel, its fracture strength and fatigue strength decrease drastically with increasing flaw size and thermal shock. To overcome these weaknesses, advanced delay-fracture high-strength bolt steels have been developed in recent years. This paper aims to introduce the development and application of advanced delay-fracture high-strength bolt steels.
High-strength bolt steels have been widely used in various industries because of their high strength and fatigue resistance, good weldability, and ability to limit exposure to creep, stress corrosion cracking, and hydrogen embrittlement. When tensile and bending stresses are applied, these steels typically exhibit a wide range of properties, ranging from very low strength to tensile strengths up to hundreds of megapascals. However, due to their inherent nature, it is difficult to prevent or significantly reduce their fracture strength and fatigue strength when cracks occur or the steel is subject to thermal shock. In order to overcome these limitations, advanced delay-fracture high-strength bolt steels have been developed and applied.
The advanced delay-fracture high-strength bolt steel has the same outstanding mechanical properties as conventional high-strength bolts, but further improves the performance of the steel under thermal shock. Specifically, the delay-fracture mechanism of these advanced steels delays the point at which the steel undergoes fracture, making it resistant to flaws and thermal shock. In addition, the steel is designed to be highly resistant to corrosion and hydrogen embrittlement, and its wear resistance is improved. Furthermore, the material has good weldability and can be used in a variety of applications, such as fastening and bridge construction.
The advanced delay-fracture high-strength bolt steel is widely used in automotive, bridge construction and other industrial applications. For example, the steel has been used in the fastening of railway sleeper clip bolts, steel structures of road bridges, suspension bridges and tower crane parts, as well as in other types of structural connections. The advantages of the steel in these applications include its strong mechanical strength and the ability to postpone fracture. Moreover, the steel can be used in a wide range of temperatures and is resistant to corrosion, hydrogen embrittlement, wear and fatigue.
In summary, advanced delay-fracture high-strength bolt steel has been developed in recent years and is now widely used in various industrial applications. This type of steel has excellent mechanical properties, good weldability, and the ability to postpone fracture point, making it suitable for use in many applications, particularly in automotive and bridge construction.
