Advanced Materials Research Vol. 764

Abstract: Nickel-based high-temperature alloy GH3039 is a kind of alloy with the poor thermal conductivity, work hardening and hard particle. It has poor machinability. The orthogonal experiment is adopted for the study on the effect of the cutting parameters on the high-temperature alloy GH3039 milling force by using the carbide tool. The milling force of the size is obtained by orthogonal cutting experiments under different cutting parameters, and analyzed the size of the cutting parameters on cutting force of law. The milling force experience formula is established by means of regression analysis. The rationality of the model is examined by using the absolute error calculation.

Abstract: The inner structure and defects of the silicon panel will influence the transfer efficiency and the stability of the polycrystalline solar cells, thus the non-destructive testing of the silicon panel is very important. In this paper, a Scan Acoustic Microscopy is applied to test the inner structure of polycrystalline silicon solar panel. From the grey image of C-Scan by the microscopy, the amplitude distribution of the bottom wave generated by the interaction between the inner grains of the polycrystalline silicon and the acoustic beam can be seen clearly. Furthermore, the defects as well as their size and position can also be tested by A-Scan, B-Scan and C-Scan with high resolution and high accuracy. The experiment results show that it is a good non-destructive method to test and evaluate the quality of the inner structure of polycrystalline silicon solar panel.

Abstract: Electrochemical micro-machining (ECMM) is a method that utilizes anode dissolution principle to process shaping. In the Electrochemical machining （ECM）of micro-hole, machining precision is an important aspect to measure machining quality of micro-hole. In this paper micro-hole machining is regarded as the research object, effects of many factors such as power supply natures, electrolyte composition, pulse width and pulse frequency on machining accuracy in micro-hole ECM have been evaluated. Research shows that processing accuracy can be improved through using non-linear electrolyte in high frequency, narrow pulse electrochemical machining.

Abstract: Formation mechanism of the micro-arc oxidation spark discharge is always a research problem; so far there isnt a theoretical model for analyzing the spark discharge formation which is widely recognized. Based on analyzing the reaction phenomena and the coating feature in the different periods of the red spark discharge, the formation model of the red spark discharge was established. The spark discharge formation mechanism is shown that it causes the spark discharge formation that the electron bombards the gas layer wrapping the coating in the infancy of red spark discharge stage; at the later period the area of strong electric field generates the spark discharge where the coating of excessive polarization turns out easily.

Abstract: In combination with the installation of radar capture camera support, the maximum offset, the rod being considered by external forces, external forces such as wind effect will produce a non-directional bend, the stability of the camera will installand capture some of the impact. Solving method in the article is a combination of the equivalent moment method to seek to solve its offset. the rod is divided into equal finite element. the equivalent moment method to calculate the relative rotation of each section. Find the maximum deflection of the rod.

Abstract: In the manufacture of ceramic components, it has been well documented that the grinding costs can be as high as 80% of the total cost. To reduce the grinding cost, massive research studies have been conducted and new types of high-performance machining techniques have been developed based on the fundamental understanding of the prevailing grinding mechanisms for engineering ceramics. The developments in grinding mechanisms and grinding processes are reviewed and summarized.

Abstract: The frame of metal wheel coated with polyurethane is made of magnesium alloy by die casting process. The coating polyurethane (soft) is made of combined material of self-skin-formation system. The permanent deformation of steering assembly is up to the international standard after accepting the specified test of axial force and steering torque; and it also accepted further special tests, including bending fatigue endurance test, torsion fatigue endurance test, and coating force test, etc.

Abstract: The fabrication process and fracture characterization of 35 and 65 vol% SiCp particulate-reinforced Al matrix (SiCp/Al) composites have been investigated. SiCp composites having different volume fractions of the n-SiCp were synthesized via by pressureless-infiltration at near-net-shape route and were uniaxially tested at room temperature. The SiC particles were mixed with silicasol as an inorganic binder in distilled water. The mixtures were consolidated in a mold by pressing and dried in two step process, followed by calcination at 1000 °C. The SiCp/Al composites were fabricated by the infiltration of Al melt into SiC performs. The experimental results show that volume fraction of reinforced particles in SiCp/Al composites had a significant influenec on fracture section surface characterization in tensile tests. Composite with 45 vol% SiCp, fracture was firstly happen in Al matrix, shallow dimples and intergranular fractures were seen in all the fractographs. With increasing of vol% SiCp, fracture was more brittle in appearance in the composites and the fracture surfaces were flat and less plastic deformations.

Abstract: The Co-base alloy laser cladding layer was coated on the 2738 mold steel surface by using the TJ-HL-5000 transverse-flow CO2 continuous laser. The morphology and hardness were investigated by metallography microscope, scanning electron microscopy (SEM), X-ray diffraction (XRD) and microhardness tester. The metallography microscope and SEM investigations show that from interface to surface along the cross section direction, the cladding layers consist of plane crystal layer, columnar crystal layer, dendrites layer and surface cellular crystal layer, respectively. XRD results indicate that the cladding layer is made of γ-Co, Cr23C6, MoC, FeCr and Co3Mo2Si phases. The micro-hardness of the laser cladding coating was about 900-1100HV1, 3 times or more of the steel substrate. And the mechanisms of microstructure formation and strengthening are investigated.