Analysis on Cracking of Steel Race Plate Surface
With the continuous development of science and technology, steel materials are widely used in the construction industry. Steel plates are widely used in bridge decks, mechanical equipment surfaces, vehicle body parts, ships, etc. These steel plates are usually surface treated to add new functions or enhance the function, such as paint or metal coating. In order to ensure the service life, the surface of the steel plate will have a certain crack tolerance, so the occurrence of cracks must be strictly controlled.
This paper mainly focuses on the cracking of the steel race plate surface. In recent years, some research on steel plate cracking has been conducted. During welding, the stress concentration caused by the welding part increases, which is easy to lead to cracking. If the structure of the plate is not considered, the stress caused by external forces will become a major factor leading to the occurrence of cracks. The cracks that occur on the surface of the steel plate can be divided into two kinds: formation cracks and tensile cracks. Formation fracture can be further divided into three categories: Strain-hardening crack, intergranular cracking and solid solution embrittlement cracking.
In the case of strain-hardening cracks, welding heat tends to make the surface brittle, resulting in cracks. These cracks are brittle, and the surface often has white spongy shape. Intergranular cracking occurs due to the welding heat, while solid solution embrittlement cracking occurs when the material is exposed to extreme temperatures, such as when welding.
In terms of tensile cracking, due to tension and thermal aspects, the effect of temperature changes is usually more prominent. In the context of temperature changes, high temperatures often lead to stress concentration. When the force exceeds the load-bearing capacity of the steel plate, the steel plate will be broken, resulting in tensile cracks.
To prevent the occurrence of cracking on the steel plate surface, measures including stress relief welding and appropriate choice of welding process can be adopted. Stress relief welding is the process of relieving the residual stress on the weldment by using the heat of annealing or slow cooling. This can help reduce the mechanical stress generated due to welding and improve the welding quality. In addition, the selection of the welding process can also improve the welding quality. In addition to annealing welding, low-heat input welding and pulsed-plasma welding are preferred. Therefore, it can minimize the generation of cracks during welding.
In conclusion, understanding the causes of cracking on the steel plate surface and taking appropriate measures can effectively prevent the occurrence of cracks and improve the service life of the steel plate surface.
