Magnetorheological (MR) elastomers are smart materials whose physical properties can undergo instantaneous and reversible change when subjected to different intensities of the magnetic field. This makes the MR elastomers have wide applications in the fields of vibration control. This work presents the vibration suppression of flexible beams with MR elastomers. An experiment system has been set up to investigate the vibration performances of a sandwich beam filled with MR elastomers. The vibration response of the beam subjected to different magnetic field intensity and excitation frequencies are demonstrated and evaluated. The results obtained indicate that vibration attenuation is achieved at different operating conditions by applying a magnetic field to the beam.

MR elastomers, which consisting of silicone rubber and carbonyl iron particles, are prepared under different magnet fields intensity. Their micro-structure and mechanics properties are investigated and compared. Results show that the bearing capacity and stiffness of both MR elastomers will increase when subjected to a magnet field. But the controllable range and comprehensive properties of the MR elastomers prepared with magnet fields are better than what of the MR elastomers prepared without magnet fields.

Temperature, load and rotate speed are the main factors which influence grease bearing life are presented by means of study on failure mechanism of grease. According to the test demands of high temperature and heavy loaded grease bearing life, test temperature, load and rotate speed of grease bearing life test are analyzed and discussed, presented that different greases should apply different test temperature. In addition, the filling amount of grease and test running mode of the grease bearing life test are discussed.

The dynamic characteristics of the grinding machines have an impact on its machining quality and cutting efficiency. In this paper, through the analysis of the structural features of the Large CNC gantry surface grinding machine, the finite element model of structure of the grinder was established on the base of the simplified machine structure, on which carried out its dynamics analysis, obtaining the modal parameters of the orders under different mode shapes. The effect on the dynamic characteristics of machine tools was analyzed under different mode shapes, then the weak link of the surface grinding machine was given, and then how to improve the structural design weakness of surface grinding machine was discussed, all of which provided theoretical basis for improvemental design for the structure of the large CNC gantry surface grinding machine.

This paper describes the experimental results of the relationship between grinding wheel topography and grinding chatter and surface waveness on the precise surface grinding machine. The inner relationship between the grinding chatter and grinding surface waveness has been analyzed. The experimental research results show that the grinding depth is a main factor which affects grinding chatter and grinding surface waveness on the grinding surface. Thus a further exploration has been made in the formative mechanism of grinding chatter and grinding surface waveness.