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The focus of this work is to investigate the ticking noise produced by the vibro-impacts between piston pin and connecting rod small head bearing. Numerical calculation and experimental verification methods were adopted and a novel method to control this intermittent noise was proposed. The dynamic model of crankshaft connecting rod piston with full floating piston pin was established and the essence of piston pin ticking was analyzed. The occurrence time of the ticking corresponded to the crankshaft angle when the resultant force of piston pin passed through the 0 axis. At the moment of impact, the peak hydraulic pressure of lubricating oil was found to be proportional to the impact strength. In order to suppress this noise, the oil groove on the bearing was designed considering the minimum oil film. After adding the oil groove, the impact intensity was significantly reduced and the noise was even eliminated. The calculated results were in good agreement with the experimental tests, and the research of this work provided a reference for controlling the ticking noise of piston pin.

For the efficient application of Terfenol-D rod, six kinds of rods were studied. Finite element software was used to simulate and calculate the hysteresis loss, eddy current loss, coil resistance, and inductance of the rods at different frequencies and currents. Three kinds of rods were manufactured, the coil resistance and inductance were measured. The results showed that the hysteresis loss, eddy current loss, and coil resistance increased, and the coil inductance decreased with the increase of frequency. As the current increased, the hysteresis and eddy current losses of the rods increased, the coil resistance and inductance remain unchanged; the hysteresis loss, eddy current loss and coil resistance of the radially slit rod were the largest, whereas that of the slit rods were larger than those of the sliced rods, the coil inductance of the slit rods was less than that of the sliced rods. The numerical calculation values of coil resistance and inductance at different frequencies and currents basically agreed with the experimental test values.

To improve the vibration performance of the Terfenol-D rod and make its work more efficient, six types of Terfenol-D rods were studied in this paper. The dynamic simulation analyses of the rods were carried out, and the core loss of the rods were calculated and analyzed. Three structures of rods were manufactured, and their output amplitude were tested. The results showed that an untreated rod had the highest resonance frequency, the largest mechanical quality factor, and the smallest output amplitude and outer surface stress; compared with the untreated rod, the resonant frequency and mechanical quality factor of the sliced and slit rods reduced, the output amplitude and outer surface stress of the sliced and slit rods increased; the resonant frequency and mechanical quality factor of the sliced rods were smaller than those of the slit rods; and the output amplitude and outer surface stress of the sliced rods were larger than those of the slit rods. The untreated rod had the largest core loss on the outer diameter surface; the core loss on the outer diameter surface of the sliced and slit rods reduced, and the core loss of sliced rods was less than that of slit rods. The radially slit rod had the largest overall core loss; the overall core loss of the radially cut and bonded rod and the sliced rods was less than that of the untreated rod and the radially slit rod.