钙磷层对NiTi形状记忆合金与骨组织结合特性的影响

用化学处理的方法 ,在NiTi合金表面生成钙磷 (Ca P)层 ,再将试样植入日本大耳兔的股骨中考察其生物相容性。试验结果表明 :经表面处理的试样和骨组织结合良好 ,并能传导新生骨的形成 ,表明经处理后有良好的生物相容性。而未经处理的试样 ,在实验范围内 ,没有观察到成骨细胞的存在及新生骨的形成     

Enhanced Oxygen Diffusion Along Internal Oxide–Metal Matrix Interfaces in Ni–Al Alloys During Internal Oxidation

A study of the internal oxidation of dilute Ni–Al alloys in an NiO/Ni Rhines pack was performed at 800, 1000, and 1100°C. Considerable deviations from the classical internal oxidation model have been observed. The rate of internal oxidation depends not only on the concentration of the alloying element but also on its nature, which contributes to determining the size, shape, orientation and distribution of the internal oxide precipitates. For instance, the precipitates in the Ni–Al alloys are continuous rods, arranged in a cone-shaped configuration that extends from the surface to the internal oxide front. The observed depths of internal oxidation for the various concentrations of aluminum are discussed and related to the morphologies of the internal oxide precipitates. The apparent N^(s) _oD_o values determined from internal oxide penetrations increase with increasing solute content in the alloy. It is postulated that diffusivity of oxygen is enhanced along the internal oxide–metal matrix interface compared with that in the metal matrix.     

扩散阻挡层对Cu-Zr纳米合金膜电阻率与残余应力的影响

用磁控溅射和离子束溅射共沉积的方法分别在以单晶硅为基体的TiN,TaN,ZrN扩散阻挡层上沉积了Cu-Zr合金膜,膜在400℃氮气中退火1h.结果表明扩散阻挡层对膜的晶体取向、电阻率和残余应力有很大影响.沉积态的膜具有强的（111）取向,且峰型严重展宽;退火后峰型明显锐化,出现（200）等晶体取向;对应TiN,TaN;ZrN三种扩散阻挡层,膜的电阻率在沉积态时分别达108,327和478μΩ·cm,退火后降至正常的数个μΩ·cm;扩散阻挡层亦可明显降低膜的残余应力,无扩散阻挡层时膜的退火应力达475MPa,有ZrN扩散阻挡层后退火应力降至149MPa.     

烧结材料孔隙形态与分布对离子氮碳共渗层组织结构的影响

研究了烧结材料孔隙形态与分布对离子氮碳共渗层组织结构的影响。试验表明，随试样孔隙数量的增加，γ＇相含量和扩散层深度增加。由于试样的正压制面与侧压制面的孔隙形态及分布不同，导致化合物层深度和相组成不同。还观察讨论了氮原子在氮碳共渗层的分布状态。     

离心铸造轧辊外层熔炼配料的优化

离心铸造轧辊生产中为了减少外层气体含量，要求尽量少脱硫降硅、甚至不脱硫降硅，为此根据外层材料成分的不同要求，在配料过程中采用不同的原材料及不同的配比，最终达到工艺要求。并介绍为达到工艺要求对所需各种原材料的化学成分要求。     

In situ observation of initial rust formation process on carbon steel under Na2SO4 and NaCl solution films with wet/dry cycles using synchrotron radiation X-rays

Atmospheric corrosion of steel proceeds under thin electrolyte film formed by rain and dew condensation followed by wet and dry cycles. It is said that rust layer formed on steel as a result of atmospheric corrosion strongly affects the corrosion behavior of steel. The effect of environmental corrosiveness on the formation process and structure of the rust layer is, however, not clear to date. In this study, in situ observation of the rusting process of a carbon steel covered with a thin film of Na₂SO₄ or NaCl solution was performed under a wet/dry repeating condition by X-ray diffraction spectroscopy with white X-rays obtained from synchrotron radiation. The present in situ experiments successfully detected initial process of the rust formation. In the early cycles, the rust constituents were not well crystallized yet, but the presence of Fe(OH)₂ and Fe(OH)₃ was confirmed. In the subsequent cycles, two different solutions resulted in difference in preferential phase of the rust constituents. α-FeOOH was preferentially formed in the case of the Na₂SO₄ solution film, whereas β-FeOOH appeared only under the NaCl solution film.     

高强钢焊接区“三点弯曲”试验拘束应力的测定

采用“三点弯曲”试验对HQ130高强钢焊接熔合区附近的应力状态进行了试验测定。试验结果表明，外加载荷增大，焊接试样的应力应变值逐渐增大，经过近似直线的弹性范围后，达到塑变区后应变发生突变。外加载荷增加使产生裂纹的可能性增大。尽管应变的公式计算值和实测值之间存在着一定的偏差，但二者的总体趋势是一致的，在要求不太严格或只要求获得应力变化规律的情况下，仍可用公式法估算。     

Sulfidation behavior of Fe-25Cr-20Ni-1.5Al2O3 in simulated coal combustion/gasification environments

The effect of minor addition of -Al₂O₃ dispersoids on the sulfidation behavior of Fe-25Cr-20Ni was investigated over a range of pO₂, 1.13×10^–20 to 1.18×10 ****^–22 atm. at constant pS₂=1.22×10^–8 atm. Fe-25Cr-20Ni and Fe-25Cr-20Ni 1.5 Al₂O₃ with and without preformed oxide scales were exposed to bioxidant gas mixtures H₂/H₂O/H₂S/Ar at 700° C. Both isothermal and cyclic exposures were included. Scales were characterized by a combination of several surface analytical tools. A remarkable improvement in sulfidation resistance is observed in Fe-25Cr-20Ni-1.5Al₂O₃ under the conditions investigated here. This is attributed to the ability of the alloy to form and maintain a predominantly Cr₂O₃ scale with reduced Fe-diffusion and content. Possible scientific reasons for such improvement are discussed. The base alloy, Fe-25Cr-20Ni, fails to develop and retain such a Cr₂O₃ scale and undergoes sulfidation within a few minutes of exposure. The scale breakdown process by sulfidation is explained qualitatively. Experimental evidence suggests that sulfur in the environment enhances Fe-diffusion and content in the scale.     

HYDROGEN TRAPPING EFFECT OF SUBSTITUTIONAL ALLOYING ELEMENTS IN α-Fe

用电化学渗氢方法测定了氢在纯Fe和Fe-Cr,Mn,Co,Si,Mo的二元合金中的扩散系数。结果表明所研究的二元铁基合金中,随着合金元素浓度的增加,氢的扩散系数降低,氢的扩散激活能增加。根据Oriani模型计算了各种合金元素的氢陷阱参数,并获得了相应的氢与陷阱结合能。按陷阱结合能由小到大的顺序是:Si,Co,Ni,Mn,Cr和Mo。最后根据合金元素引起的晶格应变场与氢的弹性交互作用和合金元素与氢的电性交互作用对结合能的本质进行了分析。     

HCP金属Mg，Ti，Zr的嵌入原子势

采用嵌入原子法，通过拟合Ｍｇ，Ｔｉ，Ｚｒ六方晶体的晶格常数，内聚能，弹性模量，空位形成能和双原子分子的键长、键能等物理参数，分别得到Ｍｇ，Ｔｉ，Ｚｒ等ｈｃｐ金属的嵌入原子势。用拟合所得的嵌入原子势计算具有相同原子体积的ｆｃｃ，ｂｃｃ结构的能量表明：ｈｃｐ结构的能量低于ｆｃｃ，ｂｃｃ结构的能量，这说明ｈｃｐ结构的势函数是稳定的。