This article focused on the microstructure characterization and residual stress measurements of the flange from classes D and C railway wheels (called 7D and 7C steel, respectively) to contribute with the residual stress level on new forged wheels flange area. A correlation with the hardness was conducted. The residual stress was measured in three points of the flange using the x-ray diffraction technique, and the microstructure characterization on SEM microscopy. We found the 7C steel has fine pearlite and ferrite microstructures, and 7D steel has degenerated pearlite and bainite microstructures. In the 7D steel, the compressive residual stress in the flange region was higher than in the 7C steel, which is related to the presence of bainite on the microstructure. There was a correlation between the hardness and residual stress value. The knowledge of the residual compression stress level is important for safety train wheels operation. The traction stress generated by the brake system on the wheel is attenuated by residual compression stress.

本文重点研究了D级和C级铁路车轮（分别称为7D和7C钢）的法兰的显微组织表征和残余应力测量，以有助于在新的锻造车轮法兰区域上的残余应力水平。进行与硬度的相关性。使用X射线衍射技术在法兰的三个点上测量残余应力，并在SEM显微镜下表征显微组织。我们发现7C钢具有良好的珠光体和铁素体微结构，而7D钢具有退化的珠光体和贝氏体微结构。在7D钢中，法兰区域的压缩残余应力高于7C钢，这与显微组织中贝氏体的存在有关。硬度和残余应力值之间存在相关性。残余压缩应力水平的知识对于安全火车车轮的操作很重要。车轮上的制动系统产生的牵引应力会因残余压缩应力而减弱。