Ceramic Wear-resistant Hard Coating Micro-finite Element Analysis Of Contact Stress

It is well known, the stress state in the contact zone is one of the most important factors for the evaluation of initation and growing of fatigue cracks .The maximum contact stress(maximum tensile stress, maximum shearing stress and maximum von Mises stress) are important factors for the design of hard coatings/substrat, because surface damage, delamination and spalling of the hard coating are usually caused by these maxmum stresses.Therefore, aqualitative analysis of these stresses is important. The aim of this paper is to describe a finite element method used to investigate the contact stresses of hard coating/substrate under fretting contact. The finite element commercial code ADINA has been used. The stresses have been computed for various values of the coating-to-substrate Young'moudelus ratio, friction coefficient and coating thickness.The main contend of the thesis is as follow:l)The character of the hard coating/substrate was analyzed.2) The distribution of cantact stress, was analyzed theoretically first and then a finite element analysis has been carried out to obtain the contact stress of the hard coating/substrate when using spherical or cylindrical fretting pads.3) The influence of values of the coating-to-substrate Young' moudelus ratio,friction coefficient and coating thickness on the distribution of contact stress(maximum tensile stress, maximum shearing stress and maximum von Mises stress) on surface subsurface and interface bonding of coating/substrate system was analyzed .it can be helpful to the design of hard coating/substrate under fretting contact.