3 results about "Rolling contact fatigue" patented technology

The present application belongs to the field of rail material research and manufacturing, and specifically discloses a rail structure for a subway humid environment. According to the distribution of pearlite lamellar spacing, the rail head cross-section structure can be divided into cap layer 1, cap layer 2, cap layer 3 and base material layer. The pearlite lamellar spacing distribution of cap layer 1 is 130-150 nm, the pearlite lamellar spacing distribution of cap layer 2 is 90-120 nm, the pearlite lamellar spacing distribution of cap layer 3 is 140-170 nm, and the pearlite lamellar spacing distribution of the base material layer is 200-230 nm. The present application designs cap-shaped structures with different depths and different pearlite lamellar spacing in the rail head. By accelerating the cooling speed of the heat treatment of the hot-rolled rail in different stages, the reasonable gradient structure distribution of the pearlite structure of the rail material is realized, the expansion speed of the rolling contact fatigue crack of the rail in the humid environment to the internal material is effectively slowed down, the rolling contact fatigue damage is reduced, and thus the comprehensive performance and service life of the rail are improved.

This invention discloses a rapid prediction method for rail rolling contact fatigue damage in the field of rail damage prediction technology. The method includes establishing a three-dimensional elastoplastic wheel-rail cyclic rolling contact finite element model, improving the cyclic plastic constitutive model, and simulating the stress-strain evolution of the rail. A rail stress-strain sample library is generated through parametric sampling and batch calculation. A Physically Constrained Generative Adversarial Network (PC-GAN) is constructed, embedding physical constraints such as contact force conservation and energy consistency into the loss function to achieve rapid and high-precision mapping from operating parameters to the stress-strain field. Based on the PC-AN prediction results, cumulative damage and fatigue life are calculated using an incremental multiaxial fatigue damage model, and a damage distribution map of the entire rail line is drawn, identifying high-risk sections. This invention deeply integrates physical modeling with intelligent algorithms, achieving an order-of-magnitude improvement in rail fatigue damage assessment efficiency while ensuring prediction accuracy, providing efficient and reliable technical support for rail life assessment and maintenance decisions across the entire rail line.

The application provides a rail rolling contact fatigue crack array detection probe based on alternating electromagnetic field, which comprises a rail, a detection probe, a shock absorber, a probe clamp and a fixing device. The detection probe comprises a special-shaped excitation module, an array sensor group and an amplification circuit. The special-shaped excitation module is adaptively designed according to the geometric shape of the rail to generate an induced current perpendicular to the crack, and the induced current has high strength and high uniformity. The array sensor group is designed in an arc shape according to the shape of the rail to completely cover the gauge angle. The shell of the detection probe is designed in a profiled shape for the rail to completely match the surface profile of the rail. The shock absorber is used to ensure that the distance between the detection probe and the surface of the rail is constant to prevent damage to the detection probe. The rail rolling contact fatigue crack array detection probe provided by the application has simple detection method, can completely cover the gauge angle in single detection, has high detection efficiency and detection precision, and can further realize surface profile imaging of rail defects.