目的 对钢球展开轮表面凹坑形微结构的几何参数(形状、大小、深度、间距)进行优化，获得增摩降磨(增加摩擦系数、降低磨损量)特性最佳的展开轮表面微结构几何参数匹配，为微结构展开轮的设计和应用提供方法和依据。方法 首先运用Hertz理论对展开轮与钢球的接触面积进行分析，确定微结构几何参数范围，设计正交试验表，并进行摩擦磨损试验;然后，基于Archard理论推导展开轮表面磨损深度计算模型，通过数值模拟获得不同几何参数情况下微结构表面的磨损深度，将仿真结果与试验结果进行对比和验证;最后，以最小磨损量和最大摩擦系数为目标函数，利用基于Pareto思想的遗传算法建立微结构几何参数优化模型，通过求解得到摩擦系数和磨损深度的最佳范围及相应微结构的几何参数匹配。结果 求解得到0.2 s时间内微结构展开轮磨损深度h为5.24×10^–7~5.32×10^–7 mm，摩擦系数μ为0.2600~0.2607，与之对应的20个非劣解中，形状系数c为0.289左右，面积s全部为0.0310 mm²，深度d为97~112 μm，大多数集中在100 μm左右，间距θ在全部间距取值范围内都有分布，其中出现频数最高的为3.59°。结论 微结构几何参数对展开轮表面磨损深度的影响程度顺序为:面积>形状>深度>间距;对摩擦系数的影响程度顺序为:形状>面积>间距>深度。展开轮表面微结构的最佳几何参数匹配:形状为菱形，面积为0.0310 mm²，深度为100 μm左右，间距为3.6°。

The work aims to optimize the geometric parameters (shape, size, depth and spacing) of the pit-shaped microstructures on the surface of the unfolding wheel, so as to obtain the geometric parameter matching of the surface microstructures with the best characteristics of increasing friction coefficient and reducing wear, and to provide methods and basis for the design and application of the microstructure unfolding wheel. Firstly, Hertz theory was used to analyze the contact area between the unfolding wheel and the steel ball, to determine the geometric parameter range of the microstructures. An orthogonal test table was designed and the friction and wear tests were carried out. Then, based on Archard theory, the calculation model of wear depth on the unfolding wheel surface was deduced, and the wear depths of microstructure surface under different geometric parameters were obtained through numerical simulation, and the simulation results were compared and verified with the test results. Finally, the minimum wear amount and the maximum friction coefficient were taken as the objective function, the optimization model of microstructure geometric parameters was established by genetic algorithm based on Pareto, and the optimal range of friction coefficient and wear depth and the matching of corresponding microstructure geometric parameters were obtained by solving the function. The results are that the wear depth h is in the range of 5.24×10–7 to 5.32×10–7 mm in 0.2 s, the range of friction coefficient μ is in the range of 0.2600 to 0.2607. Among the corresponding 20 non-inferior solutions, the shape coefficient c value is about 0.289, the area s is all 0.0310 mm2, the depth d is between 97 to 112 μm, most of which are about 100 μm, and the space θ is distributed in the whole space range, and the highest frequency of occurrence is 3.59°. The results show that the order of the influence degree of the microstructure geometric parameters on the surface wear depth of the unfolding wheel is as follows:area>shape>depth>space; the order of the influence degree of the friction coefficient is as follows:shape> area>space>depth. The optimum geometric parameters matching is as follows:The shape is diamond, the area is 0.0310 mm2, the depth is about 100 μm, and the space is 3.6°.