Advanced Materials Research Vols. 753-755

Abstract: Micro gears with different dimension were fabricated by micro metal injection molding and sintering behavior of the micro gear was investigated. For this, ultraprecision micro molds were prepared by micro electroforming. The sintered micro gears had outer diameter of 470μm and 250 μm, respectively. From the sintering results at 1200°C and 1250°C, the grain growth and the degree of thermal etching depend dominantly on the size of micro part rather than micro feature size. The sintering temperature of micro parts should be lower than that of macro components.

Abstract: In this study, a micro patterned substrate was manufactured by micro powder injection molding (μPIM). As a mold for forming the micro patterned substrate, a metal mold having a linewidth of 100 um was fabricated by micro photo etching process. The specimen prepared through such a process had a sound shape at a shrinkage rate of 16.7% with respect to the mold. To verify industrial applicability of the micro patterned substrate, a micro-fluidic device was fabricated using a smooth flow of fluid therethrough. These results indicated that the micro powder injection molding is useful for micro-fluidics.

Abstract: To establish the efficacy of creep age forming of the integrally friction stir welded panels, feasibility experiments were first conducted on friction stir welded rib-web panels of 2A12 aluminum alloys by using a designed air-loading age forming setup, and then related forming characteristics were investigated by using a mechanical-loading setup on the samples with and without friction stir welding joints. Results show that good age-formability can be observed from friction stir welded rib-web parts after creep age forming. The surface springback of the integral parts decreases with increasing the aging time and temperature. For 2A12 aluminum alloy, under an aging temperature of 190°C, a relatively better forming effect and strength can be reached at an aging time of about 8h. Compared with the non-welded structures, the introduction of friction stir welding will inhibit forming rate and will shorten the time of creep age forming.

Abstract: Radiators plays a crucial role in thermal performance of LED Lamp, and the latest development of LED honeycomb radiator forming process has been discussed. Moreover, stress-strain state in the dies and blank flow condition with different die structures have been studied by DEFORM. Accordingly the feasibility of the optimization design also has been demonstrated. The results show that the substance flowing has a serious affect on the force to the die. And with an appropriate die structure, the uniformity of forming can be greatly improved and the force to the die can be reduced.

Abstract: P/M main bearing caps are important structure parts in automotive engines. They have special shape and high precision and endure complicated load in using. After analysis the structure and property characteristics, we use Fe-C-Cu-Ni material, double-action-floating-pressing technology, liquid-phase sintering technology to develop the P/M bearing caps. After a series of test, inspection and loading test, we defined the manufacture technology of bearing caps and realized mass production.

Abstract: In this paper, based on the engineering vehicle’s side plate cold roll forming machine developed by a company, we use 3D solid modeling software Solid Works to complete the establishment of a 3D model. On the basis of explicit dynamics elastoplastic finite element method basic theory, we make numerical simulation analysis of the metal plate’s forming process by using ANSYS/LS-DYNA module. According to the simulation results, we make repeated adjustment and optimization on its pass system and parameters. Through the numerical simulation of the forming process, we conclude the stress-strain distribution of the sheet metal. For similar products, the result has a certain reference value to the research of cold roll forming process and the design of cold roll forming equipments.

Abstract: Considering the insufficient recrystallization of austenite has an effect on deformation resistance, meanwhile, referring to the plate of controlling parameters in the hot rolling process, analysis and forecast of load parameters of rolling mill and motor per pass of its rolling process. The result shows that: The production of modern steel rolling, involved in the process, equipment problems associated with rolling load, must be taken into account in its internal organization of metal in the deformation process. The less recrystallization is, the greater the deviation of the calculated results. This should be distinguished from the traditional concept of rolling.

Abstract: A feedstock consisting of carbonyl steel powder and multi-component binder was developed for powder injection molding (PIM), and the mixing behavior of feedstock was investigated under different powder loading, different temperature and different binder systems. The thermal and rheological properties were investigated. The results showed that the torque of feedstock could reach a steady state in s short time of 90 min when the loading powder was 52%. The torque of feedstock at 160°C was lower than that at 150 °C before the heating time was less 90 min. The torque of feedstock could reach steady state level in a short time of 90 min when the content of SA was 10%. SA served as surface-active agent that reduced the mixture viscosity and increased the solids content of the mixture by creating an interfacial bridge between the powder and the binder. The viscosity of feedstock decreased with increasing shear rate and temperature because the agglomerations between particles were eliminated owing to the movement.

Abstract: By comparative research and analysis of radial tire building machine with pressure-process of hot roll in 3 different heating programme of the pressure roller;Combined with thermal analysis in the Pro/MECHANICA module, Rollers by means of finite element analysis method for the model, boundary conditions and physical properties determination; Eventually through the establishment of the steady-state distribution of research, using different heating programme, through the analysis of optimal heating programme.

Abstract: The ring shape chain was shaped by twice shape at two set die at present technology of works. It should be improved in structure. At first, the bar, which was passed through a shaped ring, was orientation on the upper punch , and the elasticity upper punch and side pressure block were used in die, the bar was bended into U shape, then, the side pressure block will pressure the open ends of U shape bar , at last , a ring chain was shaped at the die. The structure of this kind of die is not complex, but, it can reduce a shape process and a shape die, also reduce a half labor time. This die has high dependability, simply use and has extremely extend value.