表面粗糙度是评定机器及仪器零件加工表面质量的重要技术指标。为了描述加工表面的粗糙度,各国采用了一系列评定粗糙度的参数,如R_a、R_2、R_t、R_p等。这些参数无疑对评定表面质量具有重要的价值。但这些参数都属微观几何轮廓垂直方向(波幅)的导出参数,也称一维粗糙度参数。它们忽略了加工表面不规则间距的信息,故不能描述 Surface roughness is an important technical index for evaluating the machined surface quality of machine and instrument parts. In order to describe the roughness of the machined surface, a series of parameters are used to evaluate the roughness, such as R_a, R_2, R_t, R_p and so on. These parameters undoubtedly have important value for the evaluation of surface quality. However, these parameters are derived parameters of the vertical direction (amplitude) of the micro-geometric profile, also known as one-dimensional roughness parameters. They ignore the irregular surface of the processing of information, it can not be described