Basic Research into the Friction Between Non-Lubricated Solid Bodies Including Elevated Temperatures

摘要

A review is given of the design and construction of a mechanically driven ultracentrifuge and of the measurements performed with this device. The reasons for discontinuing the work with this centrifuge are discussed. A newly built ultracentrifuge with transistorized drive is described; several systems for heating the rotor are shown. First measurements with this centrifuge and measuring results are described. The theoretical investigations of the separation of small particles from a solid body are based on the known laws for sinter and creep processes at elevated temperatures; they lead to an expression for the dependence of the creep rupture time on the experimental variables. The elasticity calculations furnished rigorous solutions for the vertical and tangential displacement of an elastic semi-infinite body under the action of an external pointshaped center of attraction. For the deformation of the elastic semi-infinite body by the action of an external spherical center of force with attractive and repulsive forces approximate solutions can be proposed. The appendix deals with the solution of boundary value problems of elastostatics in general and for the specific case of the elastic sphere and the elastic semi-infinite body by methods of the potential theory. (Author)