The stiffness and damping modeling of joint surfaces are important for analyzing the dynamic characteristics of bolted joints, which has a great influence on the working precision of the machine tool. In this paper, a damping model is presented to predict the tangential damping of the joint accurately. The fractal theory is introduced to characterize the rough contact surface by using fractal dimension D and fractal roughness parameter G. For each micro-contact, the contact region can be divided into stick section and slip one. The energy dissipation of the micro-contact, which can be described as the tangential damping of bolted joint, emerges in the slip section. The physics-based friction coefficient is introduced to define the energy dissipation function based on the relationship between the deformation of micro-contact and the normal pressure. The energy dissipation factor and the proportional damping of the micro-contact can be obtained. The total tangential damping of bolted joint can be obtained by integrating the whole contact surfaces. Experimental set-up is designed to verify the proposed model. Compared with the constant friction coefficient damping model, the results show that the proposed model can more accurately describe the tangential damping of bolted joint.

接头表面的刚度和阻尼建模对于分析螺栓接头的动态特性很重要，这对机床的工作精度有很大的影响。在本文中，提出了一种阻尼模型来精确预测关节的切向阻尼。引入分形理论以通过使用分形维数D和分形粗糙度参数G来表征粗糙的接触表面。对于每个微接触，可以将接触区域分为杆部和滑动部。微触点的能量耗散（可以描述为螺栓连接的切向阻尼）出现在滑移部分。引入基于物理的摩擦系数，以基于微接触的变形和法向压力之间的关系来定义能量耗散函数。可以获得微触点的能量耗散因数和比例阻尼。螺栓连接的总切向阻尼可以通过整合整个接触表面来获得。实验设置旨在验证所提出的模型。与恒定摩擦系数阻尼模型相比，结果表明所提出的模型可以更准确地描述螺栓连接的切向阻尼。