Research On Surface Roughness Measurement Based On White Light Interferometry And Stylus

Surface roughness is an important technology parameter in parts machining, it affectsstrength, lubrication and fitting of parts, and it plays a significant role in production qualitycontrol, processing technic research and material performance research. With the rapiddevelopment of the ultra-precision machining technique, more and more ultra-precisionsurfaces whose surface roughness measurement needs the nano-scale lateral resolution of theinstrument appear in modern high-tech technology and industry. The lateral resolution oftraditional stylus and interferometry is not high, and scanning probe microscopy has highlateral resolution but bad metrological characteristics, so they are hard to be used for surfaceroughness measurement of the ultra-precision surfaces. Therefore, a surface roughnessmeasurement technique based on white light interferometry and stylus is discussed in thispaper, this technique includes the atomic force probe measurement used for ultra-precisionsurfaces and the diamond stylus measurement used for engineering surfaces.The atomic force probe measurement based on white light interferometry is discussed.Microscopic interferometer system, scanning system and the atomic force probe measuringhead are designed, and the measurement program is wrote. Lateral resolution of2nm, verticalresolution of1nm, horizontal measurement range of0~60μm and vertical measurementrange in a single field of0~2μm can be reached.The diamond stylus measurement based on white light interferometry is discussed, andthe diamond stylus measuring head is designed. This method shares measurement systembased on white light interferometry with the atomic force probe measurement, and wellrealized multifunctional integration. Vertical resolution of10nm, horizontal measurementrange of0~30mm and vertical measurement range of0~20μm can be reached.Testing and certification to indication error, repeatability and stability of the measuringsystem is done, and the typical samples are measured. The experimental results show that thistechnique can used for both ultra-precision surfaces measurement and engineering surfacesmeasurement.