Study On 3D-motif Method For Surface Roughness

Micro texture of surface is a very important factor which has been considered for its quality and property characterization.And the study of the surface roughness has been the hot spot on surface engineering field with development of the instrument manufacture and measurement technology and the application of fractal,wavelet and motif theory.At the same time,the foundation of the high precision surface evaluation was laid on the industry manufacturing precision and micro mechanical manufacturing by the study of surface texture.More and more achievements have been established to be international standards or industry standards in many countries.The surface characteristics and.its link with the surface properties have been researched in this study based on the 3D-motif method.This method is a development from the 2D-motif theory with their advantage of non-filtering,unlimited by sampling length and provided a full picture of surface texture.The main contents are as follows:(1) The history of roughness assessment and advantage and disadvantage of its measurement methods are discussed.And the surface texture data by atomic force microscope(AFM) are obtained.The data file as HDF form was introduced for its wide application prospect.(2) The topological paradox has to be considered in raster representations while the motif method has change form 2 dimensions to 3 dimensions.The problem is solved by the different neighborhood connection definitions for its motif areas and the separating lines. And based on the neighborhood definitions,the surface was analysed by the watershed algorithm.(3) A new motif analyse method is presented by using four different motif structures: the elements of points,lines,surface and its body.The geometric features and the texture change by friction and wear can be described by spatial construction by motif parameters, which are selected from the four elements.(4) According to the new analyse method,a new motif combination method is presented.In this method,two motifs can be combined if their different degree is over a certain threshold.The degree is described by the parameters' distance.And the multiscale analyse curve is drawn using the Barré's algorithm.We can find that the result of parameters is just slightly difference between the Barré's method and the parameter value space.It is concluded that the new method can be applied in 3D-motif analyse.