泡沫铝制备过程中增粘剂的选择

研究了铝熔体中添加不同种类增粘剂后的增粘效果,并通过对制备泡沫体的宏观观测和微观检测,研究了铝熔体增粘方式对泡沫体结构的影响及各种增粘剂的增粘机理. 结果表明:铝熔体中加入金属钙、镁、氧化铝和粉煤灰后,其物相组成发生改变,增粘剂存在形式和增粘机理不同,得到的泡沫体在结构上差别也很大.     

提高铝合金型材表面质量的措施

从原材料、挤压工艺、模具和搬运等几个方面详细分析了影响型材表面质量的因素．并提出了提高铝型材表面质量的一些方法。     

再生铝市场前景广阔

介绍了工业发达国家废铝回收和再生铝生产情况．分析了国内废铝回收情况和再生铝生产企业分布情况。指出国内再生铝市场前景广阔。同时提出了加强废铝回收、再生利用需要解决的同题。     

ZL205A铝合金熔体净化效果分析

介绍了铝熔体中夹杂物与气体的主要存在形态及其相互作用。结合生产应用实践．简述了ZL205A铝合金熔体的净化工艺及其影响因素，提出铝液的净化应以除渣为主．去气为辅。     

Kinetics of titanium nitride coatings deposited by thermo-reactive deposition technique

In this study, the growth kinetics of titanium nitride layer deposited on pre-nitrided AISI 1020 steel samples by thermo-reactive diffusion (TRD) techniques in a solid medium was reported. Steel was at first tufftrided and then titanium nitride coating treatment was performed in a powder mixture consisting of ferro-titanium, ammonium chloride and alumina at 1173, 1223 and 1273 K for 1-4 h. Titanium nitride layer thickness on the titanium nitride coated AISI 1020 steel ranged from 5.5 to 19.2 μm depending on treatment time and temperature. Layer growth kinetics was analyzed by measuring the depth of titanium nitride layer as a function of time and temperature. The kinetics equation of the reaction has also been determined with Arhenius equation K=K_oexp(−Q/(RT). The result showed that the diffusion coefficient (K) of the process increased with treatment temperature. Activation energy (Q) for TRD process was calculated as 187.09 kJ/mol. The diffusion coefficients (K) changed between 6.637×10⁻¹¹ and 2.097×10⁻¹⁰ cm²/s depending on the process temperature.     

The influence of Y ion implantation on the oxidation behaviour of ZrN coating

The purpose of this work was to determine the influence of ion implantation on the oxidation resistance of ZrN coatings. Samples were prepared on AISI 304 stainless steel by cathodic arc deposition. They were submitted to Y implantation at 150 °C with various fluences using a metal vacuum vapour arc ion implanter. The oxidation behaviour of as-deposited and Y-implanted ZrN coatings was characterized by weight gain measurement. The oxidation resistance of the ZrN coating was reduced after it was implanted with yttrium at a low fluence but improved at higher fluence. X-ray photoemission spectroscopy and glancing angle X-ray diffraction were employed to analyze the valence states of the oxide scale and the phase composition of the oxidation layers. Yttrium implantation can greatly improve the oxidation resistance of the ZrN coating.     

PIII技术在制备c-BN硬化层中的应用

采用一种新型的等离子体浸没式离子注入技术 (PIII)在渗硼后的 5 0Mn钢试样上制备出了厚度为 0 .15～ 0 .2mm的立方氮化硼 (c BN)表面硬化层。经X射线电子能谱 (XPS)和X射线衍射分析 (XRD) ,发现硬化层中的组织有立方氮化硼 (c BN)、六方氮化硼 (h BN)、B2 O3,FeB和Fe2 B。在表层 60nm的深度范围内 ,c BN的含量较高。采用球盘式无润滑滑动摩擦实验和维氏显微硬度实验分别对渗硼 PIII复合处理以及单独渗硼的 5 0Mn钢试样的性能进行了对比实验。结果表明 :与单独渗硼的试样相比 ,经渗硼 PIII复合处理的试样具有高得多的硬度 (高达HV0 .1N44GPa)和耐磨性     

电池用含稀土铝合金阳极性能的研究

通过向 99.99%的纯铝中添加稀土及其它一些合金元素 ,如Ga,In ,Mg ,Sn ,Zn等 ,制得一系列含稀土的合金。在 2 5℃ ,4mol·L- 1 的KOH溶液中测定了它们的开路电位、自腐蚀速度与电化学性能。结果表明 :稀土元素能显著提高铝合金的抗腐蚀能力和阳极效率 ,Al 5Zn 0 0 1 5In 0 .1Sn 1Mg 0 .3RE具有较好的综合性能。     

氮化硅多孔陶瓷

国内率先报道"结构陶瓷"-"功能陶瓷"一体化的新型复合陶瓷———氮化硅多孔陶瓷,介绍氮化硅多孔陶瓷的特征和潜在应用,并展望了其研究现状与前景。     

SiCP增强泡沫铝基复合材料制备工艺及润湿性研究

对采用熔体发泡法直接制备碳化硅颗粒增强泡沫铝基复合材料进行了探索，讨论了制备过程中SiCp与铝液间的润湿性、发泡工艺参数与温度控制等对制备工艺的影喻。表明该工艺简单，易于操作，不需任何增粘措施，处理后的SiCp浸润性好且分布均匀，孔洞分布均匀。