Advanced Materials Research Vols. 189-193

Abstract: X-ray diffraction method has been employed to calibrate the stress of 6082 aluminum alloy which has been widely used among modern industrial products. Based on elastic tensile conditions, by designing rod sample of uniform intensity calibration (RSUIC), the stress measurement by X-ray diffraction method has been verificated by using elastic tensile theory calculation method and electrometric method. The results show that the stress measured by the tensile stress theoretical calculation, electrometric method and X-ray diffraction method was in good accordance with each other. And the matching relation between the surface stress measured by X-ray diffraction and the internal stress is investigated. The research will lay a foundation for the application of iXRD stress instrument for nondestructive measuring the welding residual stress of aluminum alloy.

Abstract: This article summarized depositing craft of the superficial coatings (Ni-Co-Cr-Al-Y-Si) on the Ti60 alloy (Ti-6.5Al-4.2Sn-4Zr-0.6Si) with arc ion plating technology and the oxidation behavior under 600~750 . The X-ray diffraction (XRD) and the scanning electronic microscope (SEM) were used to analyze the surface appearance, the structure and the ingredient conducts of non-coating Ti60 alloy. The contrast shows that the coatings have good protection to Ti60 alloy. The result indicated that the coating has the good oxidation resistance performance under 600°C , 650°C and 750°C . Coated Ti60 alloy oxidation resistance is markly improved. The circulation oxidation dynamics curve basically conforms to the parabola rule.

Abstract: The Ti(Y)N coatings were successfully deposited onto 18-8 stainless steel substrates by the hollow cathode discharge (HCD) ion-plating method through the application of a Ti-Y(0.2 wt%) alloy evaporation source instead of pure titanium. The influence of Y on the adhesion of the TiN coating/substrate was studied. The results show that the adhesion of the coating to the substrate was evidently enhanced by adding a small amount of the rare-earth element yttrium. The Ti(Y)N coatings deposited on some punch side pins were presented and compared with the TiN coating. The service lifetime of Ti(Y)N coated the punch side pin is approximately 50% higher compared to that of TiN coated.

Abstract: 500MPa high-strength seismic rebars was developed by nitrogen-rich & vanadium -microalloyed, controlled cooling technology in domestic steel plant of china, microalloy precipitates, microstructure, mechanical properties, welding performance and aging properties of rebars were researched by using metallographic microscopy, scaning electron microcopy, transmission electron microscopy, x-ray diffraction apparatus, flash-butt welding and mechanical properties testing. The results show that a large number of the dispersed V (C, N) precipitates are precipitated in the grain boundary, dislocation line and the ferrite matrix, precipitation size in the ferrite matrix is 10~ 20nm, V(C,N) precipitates amount accounts for 67.54% of the total amount of vanadium in steel, effect of precipitation strengthening is remarkable; when termination temperature after controlled cooling for rebars is controlled at 710°C ～750°C , the core microstructure is polygonal ferrite and pearlite, ferrite grain grade is 11.0, outer layer microstructure is acicular ferrite, pearlite and a small amount of bainite, good effects on fine-grain strengthening and seismic performance are obtained; rebars have low strain aging and good welding performance; production cost is reduced by RMB 100 Yuan per ton steel compared with VN micro-alloyed and hot-rolling process, benefit is obvious.

Abstract: The purpose of this study, using high vacuum sputtering machines, is to sputter multi-layer of aluminum nitride composite layer (AlNx) for the solar selective absorbing film. Using UV spectroscopy, gloss meter, thermometer, etc. to explore features of AlN under different wattage deposited composite layer (AlNx) . The study found that if the interference of light through the glass before exposure to the AlN compound layer (AlNx), the thermal rise rate than direct exposure to light to the composite layer of aluminum nitride (AlNx) significantly improved, its efficiency by up to 9 %

Abstract: The paper defined a concept of the utmost shapeable angle for the gas metal arc welding based rapid forming process, which is used to judge supporting material need to be employed or not when a inclined wall is deposited. If the angle formed by the outer normal of the inclined wall and building direction exceeds the sum of the utmost shapeable angle and π/2, then supporting material must be deposited to finish the inclined wall along the given building direction. The effects of metal transfer mode and welding speed on the utmost shapeable angle were studied. It is found that the ‘one droplet per pulse’ metal transfer mode in pulse-current welding based RP may obtain a bigger utmost shapeable angle than short circuit metal transfer mode does. The welding speed influences the utmost shapeable angle through heat input and bead profile. An abrupt bead is harmful to get a bigger utmost shapeable angle. Within a welding speed extension from 9 mm/s to 30 mm/s, the utmost shapeable angle gets the maximum value of 55° when the welding speed is 18 mm/s.

Abstract: Tungsten carbide cermets coating on carbon steel were fabricated by laser clad cooperation combustion synthesis method. The microstructure, phase, element distribution and microhardness have been analyzed with the aid of SEM, XRD, EDS, EPMA and microhardness-tester. It is shown that the coating consisted of WC, CW₃, W₂C, WCx, and FeNi₃. The results of hardness measurement showed that the hardness was superior to substrate. Analyze the effect of different laser power and different laser scanning speed on the quality of the laser cladding surface, the surface quality gets better with the increasing of the laser power, and gets better with the reducing of the scanning speed.

Abstract: Rapid tooling developed from the rapid prototyping technology is a new method and technology of mold making, and this paper mainly studies the composite aluminum-filled epoxy (CAFÉ) mold，which is one of the rapid bridge toolings, applied to thermoforming of the plastic parts. The material formula of the CAFÉ mold with E51 as matrix is developed, and using the formula we have made the CAFÉ mold for the back shell of a cell phone charger, which is installed at the injection molding machine to do the test and finally successfully obtain the polypropylene sample. In addition, the process of making the CAFÉ mold is described in detail in the paper.

Abstract: In the paper the efficient and low-cost plasma cladding technique has been used to prepare Fe-Ni based alloy coatings on the surface of low carbon steel. The high-temperature isothermal oxidation behavior of the specimens has been tested at 700 °C and 800 °C in air using an electrical furnace for 100 h. The elements distribution, phase composition, and morphology of the alloy coatings after the oxidation test have been characterized by SEM/EDS and XRD. Isothermal oxidation test show that the Fe-Ni based alloy coating has excellent high temperature oxidation resistance at 700 °C and 800 °C. The oxidation rate of Fe-Ni based coating at 800 °C is higher than that of at 700 °C. At 800 °C, the oxidation kinetics basically follows the parabolic rate law before 80 h. A protective Fe_0.99Fe_1.97Cr_0.03Ni_0.01O₄ and Cr_1.3Fe_0.7O₃ based oxide film has been formed on the surface of the coating after oxidation.

Abstract: Electrochemical method is applied to prepare the porous anodic aluminum oxide (AAO) membrane. After the impregnation process, nonivamide was encapsulated into the channels of the AAO membrane. We apply the electrochemical impedance spectroscopy and polarization techniques to measure the performance of the combined material. The slight solubility of nonivamide enables it to release slowly from the AAO channels. This composite AAO-nonivamide material can show multifunctional effects, anticorrosion and antifouling, to the substrate aluminum metal.