45钢表面Ni/WC复合熔覆层的形成机制

采用真空熔覆技术在45钢表面制备Ni +WC复合熔覆层并进行阶段性取样,研究镍基复合涂层的形成机制。结果表明：在45钢表面生成与基体冶金熔合、WC硬质颗粒分布均匀的Ni基复合熔覆层。整个熔覆层由4 mm厚的复合层、1 mm厚的过渡层、20 μm厚的扩散熔合区以及250 μm厚的扩散影响区组成。复合层区由WC和分解形成的富W复相碳化物包围在Ni颗粒周围组成;复合熔覆层的主要组成相有γ-Ni固溶体、Cr₇C₃、Ni_2.9Cr_0.7Fe_0.36、Cr₂₃C₆、Ni₃Fe、Ni₃Si、Ni₃B、W₂C以及C等;真空熔覆过程包括：镍基合金颗粒达到熔点(900℃)前升温阶段颗粒间微烧结颈的形成、升温达到熔点(1020℃)开始的镍基合金颗粒熔融以及保温阶段(1060℃)的熔合扩散与WC颗粒微区位置的调整。     

一种新型的加固计算机箱设计

介绍了一种新型加固计算机机箱,其独特的双层箱体结构,使它适合在各种复杂恶劣的环境条件下使用。通过设计实践,阐述了该箱体的结构特点和密封、隔振缓冲、电磁兼容等方面的具体解决方法,特别是箱体成型和综合热设计等关键技术。经环境试验和工程实际应用的检验,证明其具有较好的综合防护性能。     

同向双螺杆挤出机的共混技术

本文论述了聚合物共混须用同向双螺杆挤出机的原理、特征及不同物料的共混技术。     

造粒机模板与切粒刀对聚乙烯颗粒质量的影响

通过多年来对聚乙烯造粒系统的调查研究及现场实践，确认了聚乙烯产品质量的影响因素。选择了造粒模板与切粒刀之间的最佳匹配。     

Accuracy of a Bellows vacuum meter with an LC-generator

Errors of pressure measurement are considered. The error as a function of the pressure for a vacuum gauge rated at up to 1000 Pa is calculated as an example. It is 0.15 ≤ δp/p ≤ 0.2% over a pressure range of 14 ≤ p ≤ 1000 Pa and it increases hyperbolically up to 100% with p = 0.01 Pa. The parametric reliability of the instrument and its immunity to an accidental increase in pressure the atmospheric level is substantiated. __________ Translated from Izmeritel’naya Tekhnika, No. 9, pp. 37–41, September, 2006.     

Filtered vacuum arc deposition of transparent conducting Al-doped ZnO films

Transparent conducting ZnO:Al and ZnO films of 380-800 nm thickness were deposited on glass substrates by filtered vacuum arc deposition (FVAD), using a cylindrical Zn cathode doped with 5-6 at.% Al or a pure Zn cathode in oxygen background gas with pressure P = 0.4-0.93 Pa. The crystalline structure, composition and electrical and optical properties of the films were studied as functions of P. The films were stored under ambient air conditions and the variation of their resistance as function of storage time was monitored over a period of several months.The Al concentration in the film was found to be 0.006-0.008 at.%, i.e., a few orders of magnitude lower than that in the cathode material. However, this low Al content influenced the film resistivity, ρ, and its stability. The resistivity of as-deposited ZnO:Al films, ρ = (6-8) × 10^− 3 Ω cm, was independent of P and lower by a factor of 2 in comparison to that of the ZnO films deposited by the same FVAD system. The ρ of ZnO films 60 days after deposition increased by a factor of ∼ 7 with respect to as-deposited films. The ZnO:Al films deposited with P = 0.47-0.6 Pa were more stable, their ρ first slowly increased during the storage time (1.1-1.4 times with respect to as-deposited films), and then stabilized after 30-45 days.     

Energy transfer mechanism of GdPO4: RE3+ (RE = Tb, Tm) under VUV-UV excitation

Polycrystal of GdPO₄:RE³⁺ (RE=Tb, Tm) phosphors were prepared by solid-state method. Vacuum ultraviolet excitation and emission spectrum and the energy transfer mechanism between the host and dopants of Tb³⁺ and Tm³⁺ were investigated respectively. The emission of Gd³⁺ at 313 nm was enhanced by the strong absorption of CTS of Tm³⁺ at 180 nm in GdPO₄: Tm. It has also been concluded that the excitation of Gd³⁺ is transferred to Tb³⁺ and then emission peaks of ⁵D_J→⁷F_J of Tb³⁺ were observed.     

钨铁合金真空脱硫脱砷工艺的开发

介绍钨铁合金真空脱硫脱砷的生产工艺以及有关的影响因素。采用这种工艺，钨铁中砷的平均含量可以达到0．0352％，硫的平均含量可以达到0．0152％；合金中砷的平均脱除率可达27％，硫的平均脱除率可达76％。     

贺力氏Multi-Lab Hvdris定氢系统使用探讨及影响因素

本文主要介绍贺力氏Multi-Lab Hvdris定氢系统使用探讨及影响因素。     

贵冶VPSA制氧机作业率攻关与改造

阐述了江铜贵溪冶炼厂二期工程引进的一套3800m3/h真空变压吸附制氧机(简称VPSA)的基本原理、工艺特点,分析了实际运行过程中周期短、作业率低的主要原因,采取了相应的技术改造和维护措施。