Tightness of sealing joints with elastic-plastic coating
Based on the layered half-space stiffness model, elastic characteristics of the half space have been presented depending on the elastic characteristics (reduced modulus of elasticity and Poisson's ratio) of the coating and basic material, the thickness of a coating and a heel pattern radius. To describe a rigid rough surface, the discrete model in the form of identical spherical segment set has been applied. The segment vertexes distribution through the height corresponds to a supporting curve of a real rough surface profile. To estimate the load and the area of a contact with the penetration of a single asperity, known finite element for solving elastic-plastic problem have been used. System of transcendental equations has been obtained to determine the relative contact area and the gap density depending on the dimensionless force elastic-geometric parameter F <sub>q.</sub>. Besides, the coating thickness and the hardenable coating material characteristics - the yield strength and the hardening exponent - have been taken into account. The effect of the relative coating thickness on a gap density value is shown.