中文摘要：

针对行星滚柱丝杠副弹塑性接触问题，以赫兹接触理论及弹塑性力学为基础，建立了丝杠与滚柱单对接触模型，得出一种判断行星滚柱丝杠副是否进入屈服状态的方法。其次，基于有限元法建立其弹塑性接触的数值模型，分析了载荷与行星滚柱丝杠副弹塑性接触变形的关系。进一步的计算表明，滚柱先于丝杠屈服，且在塑性变形量较小的载荷范围内，运用赫兹公式计算接触应力仍然可行。通过对行星滚柱丝杠副的弹塑性接触分析，得出其额定静载荷对应的塑性变形量，对未来行星滚柱丝杠副的设计提供了理论依据。

英文摘要：

Aiming at elastic - plastic contact of planetary roller screw mechanism （ PRSM）, a single contact model between screw and roller is established based on the Hertz contact theory and elastic - plastic mechanics, then a method for judging whether the PRSM has entered the yield state is obtained. Secondly, the nu- merical model of the elastic - plastic contact is built based on the finite element method and the relationship be- tween loads and deformation on the elastic - plastic contact of PRSM is analyzed. Conclusions can be drawn that the roller becomes a yield state prior to the screw through further analysis, and the contact stress calculation method based on the Hertz contact theory is still feasible when the load is under a range of small plastic deform- ation. Through the elastic - plastic contact analysis of PRSM, its plastic deformation corresponding to static load rating is acquired, which provides theoretical roles for future design of PRSM.