基于微观接触力学和并行计算的齿轮摩擦学研究

With the rapidly development of the theories of micro-contact mechanics, the new computing methods, parallel computing and big data technologies, the gear contact simulations involving the microstructure can be well done. The proposed research aims to investigate gears contact for the heterogeneous material, such as M50 NiL and Pyrowear 675 steel, and contains the following tasks: (1) Build model series for gear contact with typical heterogeneous materials, including gradient materials and materials containing impurities, and derive the displacements and stresses formulas of the three-dimensional multi-layered material under a unit pressure or traction; (2) Use the parallel computing and big data processing technologies for solving the local stresses, plastic strains and related lubrication model, and further develop high-precision and fast numerical approaches; (3) Investigate the coupling effects among the graded properties, local microscopic characteristics, subsurface plastic flow, surface roughness and lubricant characteristics, and thus reveal the relations between the macroscopic gear engagement and microscopic contact behaviors; (4) Based on the experimental and theoretical researches, the gear failure mechanism for the typical heterogeneous materials will be revealed. Researches will provide the theoretical basis for the optimization design of gear materials and lay the scientific foundation for the development of new high-performance gears.

随着微观接触力学、计算机并行算法和大数据技术的发展，考虑微观特性的齿轮接触研究成为可能。本项目旨在针对非均质新型梯度材料齿轮，如M50 NiL，Pyrowear 675钢，着重进行以下研究：（1）构建典型非均质材料（包括梯度材料和含杂质材料）齿轮接触算法模型，推导三维多层材料在单位压力和切向力作用下的位移解和应力解；（2）运用并行计算方法和大数据处理技术，进行局部应力、塑性应变和润滑模型计算，提出高效高精度的数值求解方法；（3）进行多因素耦合的齿轮润滑研究，充分考虑材料梯度特性、局部细观特性、表层下塑性流动、表面粗糙度以及润滑油特性等，进而揭示宏观啮合行为与微观界面行为的影响规律和机理；（4）基于实验研究和理论模型，揭示典型非均质材料齿轮的界面失效机理。研究成果将为齿轮材料的优化设计提供理论基础，并为研制新型高性能齿轮奠定科学基础。

在本基金资助下，项目团队基于微观接触力学对齿轮摩擦学进行了系统深入的研究，包括多层材料和梯度材料的接触和弹流润滑；含杂质材料的高副接触和疲劳；两无限大半空间中特征应变产生弹性场；直齿圆柱齿轮摩擦系数、机械能量损失及微点蚀疲劳失效。主要成果包括：1）基于Papkovich-Neuber弹性势函数建立了多层和梯度材料接触和润滑模型及其快速数值求解方法；2）基于Eshelby的等效特征应变法建立任意分布杂质对接触疲劳影响模型； 3）理论推导两半空间中特征应变产生弹性场的解析解；4）利用双滚子对滚摩擦学实验模拟线接触轮齿啮合，在较大参数变化范围内设计双滚子对滚摩擦学实验，得出一个较为准确地可适用于工程实际的界面摩擦系数经验公式。通过以上研究建立了考虑实际材料微观局部特征的接触和润滑理论模型和快速算法，建立了以滑滚比为主线的齿轮摩擦学实验框架，成果为研究真实齿轮接触行为提供理论和实验指导。