The size effect of SiC particles on microstructures and mechanical properties of SiCp/Al composites produced by spontaneous infiltration technology was investigated. In this study, samples of SiCp/Al composites were fabricated using aluminum alloy ZL101 as the matrix material, and SiC particles with different sizes as reinforcement particles. The microstructures and micro-deformation of the samples were analyzed using optical micrograph, scanning electron microscope, energy dispersive spectrometer and WDW-50 respectively. The results show that the SiC particles can distribute uniformly in the aluminum matrix using the proposed method. Examing samples with different SiC particle sizes, the sample with the largest size of particle can significantly decrease the mechanical properties of the composites. Tensile strength of SiCp/Al composite increases along with a decrease in the size of SiC particles, but the ductility of the composites decreases. It was found that an obviously toughness fossa appeared in the fracture surfaces of composites, which indicated it behaviors tearing and plastic deformation characteristics.
In the notebook and clamshell mobile phone, data communication wire often requires repeated bending. Generally, communication wire with the actual application conditions, the test data cannot assess bending resistance performance of data communication wire is tested conventionally using wires with weights of 90 degree to test bending number, this test method and device is not fully reflect the fatigue performance in high frequency and light load application condition, at the same time it has a large difference between the test data of the long-term reliability of high frequency and low load conditions. In this paper, high frequency light load fatigue testing machine based on the giant magnetostrictive material and stroke multiplier is put forward, in which internal reflux stroke multiplier is driven by giant magnetostrictive material to realize the rapid movement of light load. This fatigue testing device has the following advantages: (1) When the load is far less than the friction, reducing friction is very effective to improve the device performance. Because the body is symmetrical, the friction loss of radial does not exist in theory, so the stress situation of mechanism is good with high transmission efficiency and long service life. (2) The installation position of the output hydraulic cylinder, can be arranged conveniently as ordinary cylinder. (3) Reciprocating frequency, displacement and speed of high frequency movement can be programmed easily to change with higher position precision. (4)Hydraulic oil in this device is closed to transmit, which does not produce any environment pollution. The device has no hydraulic pump and tank, and less energy conversion processes, so it is with the trend of green manufacturing.
Enhanced optical transmission of metallic nanohole arrays stimulated the blooming research efforts on plasmonics and
rich applications. Here we studied the dependence of enhanced optical absorption on geometric parameters by nanohole
arrays on gold films in infrared wavelength (8~12μm). An empirical modeling for enhanced optical absorption is
summarized (based on a great many of simulation data and deviation analysis, and its goodness-of-fit test and
significance test is acceptable), which takes consideration of not only single parameters but also interaction parameters of
geometries. Through t-test, the interaction parameters with high significance are chosen, which could give high optical
absorption, and the interaction of different parameters was evaluated via Analysis of Variance (ANOVA). Our study
represents a new guiding rule for uncooled infrared detector design.