风电内齿圈感应淬火的数值模拟及验证

Numerical simulation and experimental verification of induction hardening of wind power inner gear ring

基于电磁-热-组织-应力耦合模型,对风电齿圈感应淬火过程的温度、组织和应力进行了数值模拟,同时采用硬化轮廓对比和硬度检测验证了仿真的可靠性。根据Maxwell方程和Fourier定律计算了齿圈表面加热和淬火过程的温度场,根据等转换法和K-M方程计算了齿圈表面组织转变过程和齿圈最终硬化轮廓。最后根据热-弹塑性模型计算了齿圈感应淬火后的整体残余应力分布。结果表明,对于温度变化,同一截面齿根温度最高,齿顶温度最低,齿面温度介于两者之间。对于淬火后的组织分布,起始端和终止端的齿廓处硬化层较厚,齿根和齿顶位置的硬化层厚度略小,但中间位置的硬化层分布均匀。对于残余应力分布,齿根处轴向应力从起始端到终止端为压应力-拉应力-压应力分布,切应力从起始端到终止端也为压应力-拉应力-压应力分布;齿廓处轴向应力为压应力状态,从起始端到终止端呈中间小两端大分布,切向应力为压应力状态,从起始端到终止端呈逐渐减小分布。

Based on the electromagnetics-thermal-microstructure-mechanical coupled field,the microstructure,temperature distribution and stress of induction hardening process of wind turbine gear ring were calculated and the reliability of simulation was verified by hardened case contrast and hardness test.According to Maxwell equation and Fourier law,the temperature change of the gear ring surface during inductive heating and quenching was calculated,and then the microstructure transformation and final hardened profile of the gear ring at a specific position were calculated using the isoconversional model and the K-M equation.Finally,the residual stress distribution of the gear ring after induction hardening was calculated by using the thermo-elastoplastic constitutive equation.The results show that the temperature of the tooth root is the highest,the tooth tip is the lowest,and the tooth surface is between the two locations.In general,the hardened profile at the tooth surface is thicker,and at the tooth root and tooth tip are slightly smaller,but the hardened profile is evenly distributed in the middle of the gear surface.For residual stress distribution,the axial stress at the tooth root is compressive stress-tensile stress-compressive stress distribution from the beginning to the end,and the tangential stress is also compressive stress-tensile stress-compressive stress distribution from the beginning to the end.The axial stress at the tooth profile is compressive stress,which is distributed in small middle ends from the beginning to the end,while the tangential stress is compressive stress,which decreases gradually from the beginning to the end.