录音机零件级进模设计

通过对录音杌零件的冲压工艺性分析，介绍了确定生产该零件采用的级进模模具结构和零件排样图的过程，而且解决了同一零件上向上和向下两个不同方向弯曲。     

Solid-solution hardening and softening by Fe additions to NiAl

Solid-solution hardening in the case of a ternary alloy addition to a B2 compound with the triple defect structure has been investigated. The fact that the ternary element may occupy either of two sublattices or may affect the concentration of other types of point defects present in the material makes this a very interesting problem to consider. Ni-rich (40 at% Al), stoichiometric (50 at% Al), and Al-rich (52 at% Al) alloys were doped with up to 12 at% Fe. Lattice parameter, bulk density and hardness measurements were performed on samples quenched from 1000 °C. It was found that solid-solution softening actually occurs in the Ni-rich alloys, while hardening was observed in the stoichiometric and Al-rich alloys. The vacancy concentration was determined from the experimental data, and the site occupancies of the Fe atoms were estimated from a thermodynamic model. Through careful consideration of all point defect concentrations the solid-solution hardening and softening behaviors could be effectively rationalized.     

45钢双层辉光离子渗Cr-C工艺的研究

在45钢表面利用双层辉光离子渗铬和双层辉光离子渗碳技术，形成高碳化物含量的合金层，对该合金化渗层进行淬火、回火及耐磨性的对比试验。结果表明，在本试验的工艺条件下，渗铬层可达数百微米以上；渗Cr-C＋淬火回火后，渗层碳化物细小、弥散、均匀，渗层耐磨性达到了淬火回火GCr15钢的7．8倍。     

Sodium sulfate: Deposition and dissolution of silica

The hot-corrosion process for SiO₂-protected materials involves deposition of Na₂SO₄ and dissolution of the protective SiO₂ scale. Dew points for Na ₂SO₄ deposition are calculated as a function of pressure, sodium content, and sulfur content. Expected dissolution regimes for SiO₂ are calculated as a function of Na₂SO₄ basicity, hence generated by fuels with 0.5% and 0.05% S. Controlled-condition burner-rig tests on quartz verify some of these predicted dissolution regimes. However, the basicity of Na₂SO₄ is not always a simple function of (Na₂O) show that carbon creates basic conditions in Na₂SO₄, which explains the extensive corrosion of SiO₂-protected materials containing carbon, such as SiC.     

SY300电解槽技术的开发与生产实践

本文通过对256台SY300(300kA)电解槽的设计和在河南豫港龙采铝业有限公司200kt/a电解系列的生产实践进行剖析，应用多模式智能控制技术和“四低一高”操作工艺。电解槽运行平糖、高效。三场设计合理．实际测试和设计值吻合。实践证明。SY300电解槽从设计到生产都已达到国际先进水平。     

The Al–R–Mg (R=Gd, Dy, Ho) systems. Part I: experimental investigation

Key experiments were carried out on the three Al–R–Mg (R=Gd,Dy,Ho) systems and the results obtained used for the thermodynamic optimisation reported in a separate paper in this issue [Caccasmani G, De Negri S, Saccone A, Ferro R. Intermetallics this issue.]. The samples were characterized by differential thermal analysis (DTA), X-ray powder diffraction (XRD), light optical microscopy (LOM), scanning electron microscopy (SEM) and quantitative electron probe microanalysis (EPMA). The isothermal sections at 400 °C are all characterized by extended homogeneity regions at a constant rare earth content. The extension of the (Mg,Al)R solid solution, cP2-CsCl type, varies with the R atomic number. Ternary compounds (τ) of Al₂(R,Mg) stoichiometry (hexagonal Laves phases with MgNi₂-type structure) have been found to exist at 400 °C in all the systems. Their temperatures of formation were detected by DTA measurements.     

二通插装阀在锻造自动线机械手液压系统改造中的应用

为解决故障率高、控制精度低的缺点,利用插装阀和PLC技术对锻造自动线机械手液压系统进行了改造,设计了插装阀式液压系统,分析了系统工作原理和改造的技术、经济可行性,取得良好的使用效果.     

纳米TiN改性Ti(C,N)基金属陶瓷的抗热震性能

为研究不同粘结相对纳米TiN改性Ti(C,N)基金属陶瓷抗热震性能的影响,真空烧结制备了粘结相质量分数分别为20%Ni、10%Co-10%Ni和20%Co的Ti(C,N)基金属陶瓷。采用扫描电镜研究了材料的组织,并测量了力学性能。采用压痕-急冷法主要研究了其抗热震性能,结果表明,随着温度的升高和热循环次数的增加,裂纹增长,粘结相为Ni的金属陶瓷的抗热震性优于粘结相为Co的金属陶瓷。显微照片表明,裂纹主要沿硬质相/粘结相界面及粘结相扩展。     

Surface modification of spherical LiNi1/3Co 1/3 Mn1/3O2 with Al2O3 using heterogeneous nucleation process

To improve the cycle stability at high voltage and high charge/discharge rate, spherical LiNi1/3Co1/3Mn1/3O2 was coated with Al2O3 by using heterogeneous nucleation process, and the physical and electrochemical properties were studied. The SEM images show that there is a uniform coating on the modified spherical LiNi1/3Co1/3Mn1/3O2. The electrochemical tests indicate that the properties of LiNi1/3Co1/3Mn1/3O2 coated with 0.5% aluminum oxide are the best. The initial capacities are 150 and 173 mA.h/g at the rate of I C in the voltage range of 2.7-4.3 V and 2.7-4.6 V, respectively, and the discharge capacities maintain about 99% and 85% after 30 cycles, respectively. While those of the bare LiNi1/3Co1/3Mn1/3O2 are only 90% and 75%, respectively. The CV tests of LiNi1/3Co1/3Mn1/3O2 show that Al203-coating can restrain the oxide-reduction peak currents fading during the charge/discharge course.     

Microstructure and formation mechanism of titanium matrix composites coating on Ti-6Al-4V by laser cladding

Laser cladding experiments were done on a 5-kW continuous wave CO2 laser to synthesize TiC and TiB rein- fowed titanium matrix composite coatings on Ti-6AI-4V alloy with a mixture of Ti and B4C precursor powder. The ther- modynamics of the reactions were calculated and analyzed. The microstructure and phase evolution of TiB and TiC com- posites were investigated. The results showed that the chemical reaction between Ti and B4C would release much heat, and these compounds, TiC, TiB, and small amount of TiB2, can be formed on the surface of Ti-6AI-4V alloy if the supplied en- ergy is sufficient to excite the reaction among the initial products. A good metallurgical bond between the coating and the substrate can be achieved. The microhardness of coating was irregular and the maximum value was approximately HV600.