Incompliete Contact And LZ50Axle Steel Fretting Fatigue Strength Relation Research

With the development of China’s high-speed and heavy-load railways, we have higherrequirement to the safety of railway axle. An axle is assembled with a wheel by interferencefit, withstand all external load, So axle fatigue has been attached great importance to therailway department. And in order to ensure the required run-up to the national reliability onthe basis of economic and scientific, so it is necessary to carry out detailed researches onfatigue strength of axles, and find a effective preventive countermeasures.This paper first analyzed the stress field in the incomplete contact interface edge byusing the finite element method; consider the impact of coefficient of friction, materialcombinations, the transition radius of the circle, as well as the external load incompletecontact interface edge stress field. The singular stress fields near the contact edge are obtainedby using finite element method and solving the sliding contact interface edge stresssingularity of the characteristic equation method.Then, the circumferential stress distribution along the-180°to0°is obtained by usingfinite element method, consider the impact of coefficient of friction, the transition radius ofthe circle, external loads and material combinations to the circumferential stress field, basedon the Leeds parameters Ruiz crack initiation criteria obtained Keys interface end frettingfatigue crack initiation location along the endless Keys interface Ruiz maximum, thismaximum shall finish.We can use the fatigue testing machine for fatigue testing two incomplete contactcomponents, and obtained the relationship between stress intensity factor and life,experimental verification of the above methods.Then, this paper takes the axle/hub assembly as a research object. Axle interference fitelasticity analysis and finite element analysis to evaluate the amount of interference axlecontact. And considering the axle under load, external load, the transition radius of the circleand the amount of interference hub endless Keys interface end circumferential stress field, thestress intensity factor is then calculated according to the extrapolation formula, andinterference transition radius of the circle and the external loads on the stress intensity factor.Finally, the axle of the crack initiation life was evaluated.