About Full Fatigue Curve

Abstract

The review is given and methods of a schematization of full fatigue curve on base to 10 7 cycles and to 10 9 cycles are analysed. It is shown that the question on its construction is debatable. For experimental check the generalised schematization of full fatigue curve offered in work [17] is accepted. In article the basic methodical principles of carrying out of correct fatigue tests (in a wide range of change of durability) are formulated. Their realisation has led to construction of the generalised curve consisting of 4 sites: quasistatic (I), smallcyclic (II), multicyclic (III) and high-resource (IV) fatigue. In work the analysis of the received results is given. In particular, it is shown that approximation of sites by the known sedate equation states a comprehensible estimation of fatigue durability. It is offered to characterise system of key parametres of a limiting condition two numbers (σ lim (N σlim)) which define as value of fatigue strength (σ lim) for this site, and durability (N σlim) at which it is reached.

Keywords

• mechanical
• quasi-static
• low cycle
• multicyclic
• high-resource fatigue
• complete fatigue curve
• sample
• limit of endurance
• durability (number of cycles to failure)