| Surface topography of mechanical accessory affects not only its using capability, but also its quality,reliability and life. With the rapid development of modern manufacture technology, we require more and more good surface quality in many productions. Super-exact machining technology has have becoming a forward of modern manufacturing technology. Super-testing technology is a high-tech of Super-exact machining technology, so testing super-exact surface micro-topography has became a key problem in the field of super-exact manufacture. However, the appearing of SPM provides a method in settling the problem for us. Scanning probe microscope(SPM) has been promoting ultraprecision machining and its measure dramatically since it came into the world in 1986 which enable researchers to study the ultraprecision surface structure and function. SPM has higher than a kite resolving power, and is capable of observing and describing super-exact manufacturing surface. We obtain much important surface information through analysis and research for kinds of testing phenomenon of surface quality. In the latest years, many SPM are applied for super-exact manufacturing and measuring fields.Lately, the new development is obtained in evaluating technology of super-exact surface and layer integrality, and it is very active in the researches of 3D surface topography testing and analyzing. In particular, the invention of STM and AFM provides a possibility for surface topography observation in nanometer-scale. The techno-optics researches much more catch our eye. Based on the gradual maturation of kinds of measuring methods, The touching-instrument introduces "light-needle" for changing disadvantage of itself. In addition, with the rapid development of fractal geometry,wavelet analysis,image disposal and character identify technology, it shows quite potential in 3D surface characteristic research.Mostly research of this paper is how to improve precision of SPM and assess super-exact surface micro-topography. I test super-exact surface micro-topography by SPM, so that I find that some factors affect testing precision of SPM by experiment. I study the factors by the numbers, Then dispose scanning image, finally assess super-exact surface after cryogenic polishing without abrasive. Mostly researches are as follows.Firstly, I compare testing effects of WYKO with SPM, and draw the conclusion. Appling to test, WYKO is big in sampling area, and is able to reflect externally surface Ra of the workpiece, but go against detail analysis of micro-topography. SPM is small in sampling area, even more apply to test surface micro-topography, and is helpful in researching machining mechanism of super-exact surface.Secondly, starting with the frame of SPM, I have studied piezoelectricity error and frame error of piezoelectricity scanning,frame error of measuring system,needlepoint shape and outside vibration, and analyze by the numbers error factors of affecting measuring precision. Then based mechanics model in needlepoint and sample from librating analysis aspect, compared the testing effects after acceding to a damping flat roof. I study what modality of the error factors are in measuring affect, and put forward how to settle. Through the experiment of scanning piezoelectricity error and frame error, draw the conclusion: Owing to the affect of scanning piezoelectricity error, SPM requires that workpiece Ra less than 100nm, its scanning area is not suitable over bigness. Piezoelectricity variety makes scanning image unstabilization in beginning, so image is collected after 3~4 minute. Owing to the affect of scanning frame error, when the scanning area is less than 60μm×60μm and the needle length is more than 4mm, is less. of x axes will minish, when largen. of x axes will largen, when largen. of y axes almost largen linearly when largen. of y axes is foreign to . Therefore, reasonably optimizing scanning frame parameter can debase the affect of two errors, so that improving precision of SPM. The needle shape impacts weighti...
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