An Analysis of the Elastic and Plastic Deformation of Machined Surfaces in Contact : 4th Report, Deformation of Contacting Rough Surfaces when Directional Asperities and Nondirectional Ones are in Contact

Abstract

When machined surfaces are divided into directional asperities and nondirectional ones, the analysis of normal deformations at metal joints are classified as follows. (i) Contact between directional asperities and a flat surface. (ii) Contact between two surfaces with directional asperities whose directions are crossed each other. (iii) Contact between two surfaces with nondirectional asperities. (iv) Contact between directional asperities and nondirectional ones. In this report, the elastic deformation and the plastic one for the 4th case were analyzed. Projections of directional asperities and nondirectional ones were assumed as wedge shape and conic one respectively. The elastic deformation and the plastic one at metal joints were synthesized by statistic of surface asperities in contact. Results were as follows. (1) Relation between the deformations and the normal pressure is linear on a double logarithmic paper. (2) The deformations are classified by the contact surface coefficient.