活性酯硬化水玻璃砂的研究

用焙烧活性砂混制而成的活性酯硬化水玻璃砂与普通酯硬化水玻璃砂相比，强度成倍提高，从而减少水玻璃的加入量，改善水玻璃砂的溃散性。实验证明：原砂的表面活性直接影响在水玻璃砂中水玻璃的加入量，是改善水玻璃砂溃散性的关键之一。焙烧活性砂的水玻璃加入量只要１．５％～２．０％，即能满足实际生产的强度要求。     

Effects of temperature and blank holding force on biaxial forming behavior of aluminum sheet alloys

Biaxial forming behavior is investigated for three aluminum sheet alloys (Al 5182 containing 1% Mn (5182+Mn), Al 5754, and 6111-T4) using a heated die and punch in the warm forming temperature range of 200–350 °C. It is found that, while all three alloys exhibit significant improvement in their formability compared with that at room temperature, the non-heat-treatable alloys 5182 + Mn and 5754 give higher part depths than that of heat-treatable 6111-T4. The formability generally increases with decreasing BHP (BHP), but increasing the forming temperature and/or BHP minimizes the wrinkling tendency and improves the forming performance. The stretchability of the sheet alloys increase with increasing temperature and increasing BHP. For the alloys and forming conditions involved in the current study, the formability, measured in terms of part depth, comes mainly from the drawing of metal into the die cavity, although stretching effects do influence the overall forming behavior. The optimum formability is achieved by setting the die temperature 50 °C higher than the punch temperature to enhance the drawing component. Setting the die temperature higher than the punch temperature also improves the strain distribution in a part in such a manner that postpones necking and fracture by altering the location of greatest thinning.     

Model of intense pulsed ion beam and simulation study of energy deposited on target

Gaussian type models have been established according to the real detected voltage of magnetically insulated ion diode and intense pulsed ion beam density near the focus of the diode. The energy deposition of Al target irradiated by intense pulsed ion beam has been simulated by Monte Carlo method based on these models. The results of energy depositions of the irradiation of single energy ions and the Gaussian distribution IPIB have been obtained. Especially cases of ion beam irradiating Al target at different angles on one dimension and two dimensions are discussed. The evolution processes of the energy deposition of ions in target have been simulated during a pulse. In addition, incident angles of H⁺ ions and C⁺ ions ranging from 20 to 40° have been researched. We obtained the conclusions that C⁺ ions of the beam affect the physical properties of near surface region, but H⁺ ions affect the deeper layer. The energy of intense pulsed ion beam mainly deposits on target surface, so melting and evaporation begin both from target surface.     

Development of microstructure and mechanical properties of a Ni-base single-crystal superalloy by hot-isostatic pressing

Effects of the hot-isostatic pressing (HIP) process on microstructures and mechanical properties of Ni-base single crystal superalloy CMSX-4 were investigated. In the overall heat treatment process, the HIP treatment remarkably induced the healing behavior of micropores and decreased the pore size and porosity of superalloy CMSX-4 compared with normally treated specimens. The microstructure of γ′ phase after the HIP process showed rather a coarsening tendency and could be developed by the partially solution and aging treatment. Consequently, the elimination of cast micropores using the HIP step resulted in the inhibition of crack initiation in microstructure and improved the stress-rupture lives of Ni-base single crystal superalloy by 185%.     

Effects of phosphorus addition on the magnetic properties of sintered Fe-50 wt.% Ni alloys

Phosphorus was added to Fe-50 wt.% Ni in the form of a coated composite powder via an electroless plating process. Addition of phosphorus to Fe-50 wt.% Ni facilitated increases in density and grain size, both of which were beneficial to magnetic performance. Because of the homogeneous distribution of phosphorus in the powder, the optimal phosphorus addition was much lower than for those using Fe₃P as the phosphorus precursor. The optimal phosphorus addition was close to its maximum solubility in Fe-50 wt.% Ni (about 0.5 wt.%), above which precipitation of excessive phosphorus in the form of iron nickel phosphide, (Fe,Ni)₃P, effectively degraded the magnetic properties of Fe-50 wt.% Ni. Without the addition of phosphorus, good magnetic properties could be achieved only when the sintering temperature was high enough (>1200 °C) to result in a high sintered density and large grains in the sintered structure.     

Numerically optimal design for the system with coupled complex transport phenomena-application to the Submerged Entry<Emphasis Type="Italic">Nozzle</Emphasis> in continuous slab caster

This study presents a simple and robust algorithm for the optimal design of the system with coupled complex transport phenomena: the transport phenomena comprise fluid flow, heat and mass transfer. The (1+1)-Evolution Strategy method is adopted as the optimization method. In order to analyze the transport phenomena in the complex geometry generated during the optimization procedure, thefinite volume method with a boundary fitted curvilinear coordinate system is used. To confirm the validity of the present method, the optimal design for the inner shape of the simplified two-dimensionalSubmerged Entry Nozzle in the continuous slab caster is conducted. It is shown that the resulting design of the nozzle is consistent with the purpose and constraints of the design.     

现代化中厚板热处理机组及其使用效果

介绍了引进的辐射加热无氧化辊式热处理炉及连续辊式淬火机，有效地解决了钢板的表面质量问题，取得了满意的效果．     

The Structure Stability of Carbide-Free Bainite Wheel Steel

Metallographic structures of carbide-free bainite steel wheel rim are mainly composed of supersaturated lath ferrite and retained austenite film among bainitic ferrite laths. It is suspected that supersaturated ferrite and retained austenite are likely to decompose under the influence of temperature change and mechanical stress. Stability of wheel rim structure is studied by means of x-ray diffraction, dye microscopy, and micro-hardness test. When the samples are tempered in the range of 150-350 °C, the retained austenite films are at the state of relative stability. Fifty percent of retained austenite is decomposed when the sample is tempered at 400 °C. Microhardness increases when the sample is tempered at 150 °C. The decrease in hardness is mild when the samples are tempered from 200 to 500 °C. The mechanical stability of retained austenite film is studied with tensile sample under the effect of tensile stress. The retained austenite appears to be stable in low and middle degree of deformation, and decomposition occurs at great amount of deformation. Diffraction peak of carbide is not found in all above experiments. The steel enriched silicon prevents the carbide precipitation during the transformation. It indicates the carbide-free bainite wheel steels have an excellent thermal and mechanical stability.     

论大学生诚信教育

大学生诚信教育是社会主义市场经济发展的需要，也是大学生个人健康成长的需要，对构建“和谐社会”具有战略意义。当前大学生诚信缺失有其深层次原因，包括社会环境的影响、道德教育的软弱、监督机制的缺失等。应积极探索和实践大学生诚信教育途径，努力扭转大学生诚信缺失的现状，创设诚信校园和诚信社会。     

Influence of the stress,strain, and temperature on the surface roughness of an AlSl 52100 steel due to an orthogonal cut

In recent years, the finite element method (FEM) has become the main tool for simulating the metal cutting process because research based on trial and error is time consuming and requires high investment. Early studies were done by different investigators. In this research AISI 52100, hardened steel (62 HRC) was selected for an orthogonal machining process as well as metal cutting simulation using the software DEFORM-2D. This software is based on a forging process and has been adapted to an orthogonal machining process. The results of simulated cutting forces were compared with experimental cutting force data to validate the orthogonal cut simulation. Also, the surface roughness was measured, and the influence of the stress, strain, and temperature on the surface roughness was studied.