Different fabrication techniques for NiTi alloys, such as three dimension bulk (vacuum melting, combustion synthesis, powder metallurgy, precision casting, solid-phase diffusion), two dimension thin-film (sputter deposition, rapid quenching, impulse laser deposition), one dimension fibre (clustered drawing) and zero dimension powder (reductive diffusion, molten salt synthesis) are summarized, and their applicability, advantages and disadvantages are also reviewed. Based on mentioned above, the developmental direction of fabrication techniques for NiTi alloys is prospected.

对经过不同表面处理的钛镍合金丝材的力学性能进行了对比分析. 研究表明: 与酸洗及机械抛光相比, 电解抛光可有效改善钛镍丝材的力学性能, 而经电镀工艺处理后的试样则易发生氢脆现象, 从而显著降低材料的力学性能指标.

使用氢气还原氮化法, 以针状γ-Fe2O3为原料在不同温度下制备了 Fe4N 吸收剂,研究了氮化温度对吸收剂形态的影响,并对 Fe4N 吸收剂+环氧树脂+固化剂组成的吸波材料进行了电磁参数与吸波性能的测试.在 540℃制备的 Fe4N 吸收剂可以实现较高的吸收剂体积分数,从而可以实现高的磁导率值,通过合理的设计,由该材料制备的 2 mm 厚的吸波材料在 3GHz 反射率低于-18 dB.

1 钛的基本性能 钛的原子序数是22,是第四周期第四副族(即ⅣB族)元素,密度为4.51g/cm3,仅约为铁的57%.钛合金具有很高的比强度,某些钛合金能在550 ℃和-250 ℃长期工作,是大型客机和先进战机的关键用材,所以人们常把钛称作"太空金属".

本文对NiTi合金的电解抛光机理进行了初步的探索.研究表明:NiTi合金的电解抛光特性曲线与典型的电解抛光特性曲线有显著不同,不存在稳定的电流平台区.当试样在低电位区抛光时,抛光速度为反应产物通过粘滞层的扩散速度所控制;而当试样在高电位区抛光时,则以点蚀机制为主.

A new method was established to separate and determine Cu0 incuprous oxide products. The influence of concentrations of concentration of HCl and SnCl2, and soaking time on solubility of Cu0,Cu2O and CuO was studied. The RSD was below 1.0%.

Using copper electrodes,cuprous oxide powder was prepared by electro-synthesis method in alkaline solution of sodium chloride. The operating conditions such as the comcentration and temperature of electrolyte,anode current density and additive were studied one by one. The optimum conditions for preparing cuprous oxide were established as follows:［NaCl］=260-290g/L,［NaOH］=0.5g/L(i.e.pH=12.1),temperature,80℃,anode current density,750～1000A/m2,［Na2Cr2O7］=0.05g/L. Under this condition,cuprous oxide powder well within GB1620-79 was obtained.

对W-Ni-Fe高比重合金的金相组织、力学性能以及微区成份分布进行了观察分析,讨论了氧含量对合金组织结构及机械性能的影响.

The effects of temperature (1650~2250'C) time (20~180 min), particle size of WC (1~13 urn) and that of TiO2(l~7 urn) on the formation process of solid solution Tio.5W0.5C have been investigated by X -ray diffraction, optical microscopy, SEM and EPMA methods. It is found that the formation of (Ti,W)C is controlled by diffusion process between WC and disequilibrium (Ti,W)C. According to Jander and Arrhenius equation, the apparent activation energy was calculated to be 318~380 kJ/mol (for T<1850'C) and 100~ 117 kJ/mol (for TJ&ISSO'C). The diffusion model for different temperature interval was proposed. An Xray diffraction calculating index H was also developed to examine the micro-inhomogeneity of (Ti,W)C. H value variation agrees well with the experimental results.