Clarification of the sliding contact wear mechanism between thin coated magnetic disc and head

为了阐明薄涂层磁盘与磁头接触的滑动接触磨损机理，本文对实际带磁头磁盘的相似模型进行了以下试验和分析研究：1.实际带磁头磁盘的相似模型的摩擦磨损试验对三种溅射Cu的涂层磁盘进行了销盘磨损试验，Ti和SiO_2在1 mm厚的铝基圆盘上在小载荷60 g-500 g下的沉积。头部被模拟为由不锈钢制成的销，并且测量由于摩擦热引起的销的摩擦系数和温度。作为该实验的结果，对于每种涂层材料，获得摩擦系数值为0.2〜0.6。从温度场的计算结果可以看出，摩擦热的分布和传递与涂层材料和销材料的导热系数之比成正比，并可根据该值估算出摩擦系数 关于我们 2.涂层圆盘旋转滑动时的机械应力和瞬态热应力分析利用摩擦系数和摩擦热的实验结果，对涂层圆盘的机械应力和瞬态热应力进行了分析，并对其分布进行了数值计算。径向和周向热应力显示了接触载荷下基体金属拼接表面上的最大压应力，并显示了盘背面上的最大拉应力。载荷方向的机械应力显示最大压应力均匀分布在厚度上。摩擦载荷引起的剪应力在圆盘的两个表面都出现最大值。3.表面裂纹的应力强度因子和裂纹扩展的断裂力学分析作为一个实际的失效例子，考虑了具有多个表面裂纹的涂层材料。分析了应力强度因子，从断裂力学的角度考虑了裂纹扩展.结果表明，由于裂纹间的相互干涉，应力强度因子的大小随裂纹间距离的减小而减小，且干涉效应与涂层材料无关。少

In order to clarify the sliding contact wear mechanism of a thin coated magnetic disc being in contact with a head, following experimental and analytical research were carried out for the analogous model to the actual disc with a head.1.Friction and wear test of the analogous model to the actual coated disc with a headThe pin-on-disc wear test were carried out for three kind of coating discs spattering Cu,Ti and SiO_2 on the Al based disc with 1mm thick under small loading 60g〜500g. The head was modeled as a pin made of stainless steel, and the frictional coefficient and temperature of pin due to frictional heat were measured. As a result of this experiment, the value of frictional coefficient is obtained as 0.2〜0.6 for each coating materials. From the result of temperature, it is suggested that the frictional heat is distributed and transferred in proportion to the ratio of thermal conductivity of coating and pin materials, and the frictional coefficient can be estimated by the value … More of steady temperature.2.Analysis of mechanical stresses and transient thermal stresses of coating disc due to rotating slidingUsing the experimental results of frictional coefficient and frictional heat, mechanical and thermal stresses in coating disc are analyzed and their distributions are calculated numerically. The radial and circumferential thermal stresses show the maximum compressive stresses on the splicing surface of the base metal beneath the contact load and show the maximum tensile stresses on the back surface of the disc. The mechanical stresses of load direction show the maximum compressive stresses distributed uniformly over the thickness. The shearing stresses due to the frictional load show the maximum value at the both surface of the disc.3.Fracture mechanics analysis for stress intensity factors of the surface cracks and crack growthAs an actual failure example, the coating materials with multiple surface cracks are considered. The stress intensity factors are analyzed the crack growth are considered in the fracture mechanics viewpoint. It is shown that the magnitude of stress intensity factors decrease with a decrease of the distance between the cracks due to the mutual interference and the interference effect is independent of coating materials. Less