高铁轴承环组织性能控制成形技术基础研究

High-speed rail bearings in our country are all made by foreign corporations, which is not conducive to the healthy development of national economy and the national security. Outer and inner rings of high-speed rail bearings play important roles on the lives and performances of high-speed rail bearings because they constitute the main body of high-speed rail bearings. For our high-speed rail bearing rings, the metal streamlines don’t distribute along the raceways and the grain size is larger one level than that of high-speed rail bearings abroad. For this purpose, through theoretical calculation, numerical simulation and testing of the hot rolled-thermomechanical treatment, we plan to research the macroscopic forming mechanism of controlling metal streamlines in hot rolling of high-speed rail bearing rings. Further, we will reveal the effect of hot rolled-thermomechanical treatment on the fine-grained microstructure and its uniformity for high-speed rail bearing rings. On the basis of these studies, we can develop the controlled forming theory and technology of metal streamline and fine-grained microstructure of high-speed rail bearing rings through establishing the design methods of die and blank, metal streamline and fine-grained microstructure, and hot rolled-thermomechanical treatment.

我国高铁轴承全部依赖进口，这不利于我国经济健康发展和国防安全。高铁轴承内外环件构成轴承本体，直接决定了高铁轴承的性能和寿命。我国高铁轴承环金属流线没有沿着滚道分布，晶粒组织比进口高铁轴承晶粒组织粗大一个等级。为此，本项目通过理论计算、数值模拟、近形热轧成形和热处理实验，研究高铁轴承环金属流线控制近形热轧宏观成形机制，揭示近形热轧-形变热处理工艺条件对高铁轴承环细晶组织状态及其均匀性的作用规律，建立高铁轴承环模具和毛坯设计方法、金属流线和细晶组织状态设计方法、近形热轧-形变热处理工艺参数设计方法，形成高铁轴承环金属流线沿滚道分布的近形热轧成形和热轧-形变热处理的细晶组织控制成形理论和技术设计方法。

我国高铁轴承全部依赖进口，这不利于我国经济健康发展和国防安全。高铁轴承内外环件构成轴承本体，直接决定了高铁轴承的性能和寿命。我国高铁轴承环金属流线没有沿着滚道分布，晶粒组织比进口高铁轴承晶粒组织粗大一个等级。为此，本项目通过理论计算、数值模拟、近形热轧成形和热处理实验，研究高铁轴承环金属流线控制近形热轧宏观成形机制，揭示近形热轧-形变热处理工艺条件对高铁轴承环细晶组织状态及其均匀性的作用规律，建立高铁轴承环模具和毛坯设计方法、金属流线和细晶组织状态设计方法、近形热轧-形变热处理工艺参数设计方法，形成高铁轴承环金属流线沿滚道分布的近形热轧成形和热轧-形变热处理的细晶组织控制成形理论和技术设计方法。.以高铁轴承为研究对象，分析了轧制成形变形量对轴承晶粒细化、塑形损伤和织构演化的作用规律，揭示了高铁轴承环件周向和轴向组织演化与轧制工艺的相互作用关系，确定了轧制工艺参量选定依据；提出了一种金属流线沿滚道分布的高铁轴承环成形工艺方法，能够直接成形高铁轴承环滚道使金属流线沿着滚道分布，避免了较大加工余量切削降低材料利用率和切削加工切断金属流线；提出了高铁轴承环轧制环坯及环坯设计方法，使环坯中间金属体积较大填充芯辊型腔，热轧成形的高铁轴承环晶粒细化均匀，提高了高铁轴承环细晶强韧性能；提出了高铁轴承环热轧成形驱动辊的改进方法，通过改进驱动辊结构，补偿高铁轴承环凹陷位置金属，减小切削加工余量，提高了金属利用率，降低了环件生产成本；设计了一种高铁轴承环压力淬火模具组件，在脱模时该组件使模具闭合间隙消除，方便模具顺利脱出，减少磨损，设计弧形凸圈与内锥面之间形成线接触，便于高铁轴承环均匀冷却、脱模，减少磨损。研究成果为高铁轴承环细晶强韧组织性能控制成形方法提供了理论依据和技术支撑。