APPLICATION OF COMPUTER NUMERICAL METHOD IN PORE STRUCTURE CALCULATION

This paper compares the results Of calculat-ing pore structure and graphing differential and integralpore size distribution by hand and Computer,and presents thatlagrangian interpolation uesd by calculating pore structure issuitable and reliable.     

氮离子注入尼龙1010的摩擦学特性

用高能离子注入机对尼龙 10 10进行 N+注入改性 ,注入能量为 4 5 0 ke V,剂量分别为 5× 10 14 /cm2 、2 .5× 10 15/cm2 及 1.2 5× 10 16/cm2 。以 Zr O2 及 Si3N4 球为上球样 ,分别与注入尼龙 10 10下盘样组成摩擦副 ,在销盘摩擦试验机上评价它们在干摩擦条件下的摩擦磨损行为。结果表明 ,几种剂量的 N+注入均增强了尼龙 10 10的耐磨性。未注入样品的磨损主要表现为粘着、塑性变形、犁沟和疲劳脱层 ,注入样品的磨损主要为轻微的磨粒磨损。     

Electrical properties of La0.6Sr0.4Co1-yFeyO3 cathode material

The electrical properties of La0.6Sr0.4Co1-yFeyO3 （LSCF, y=0-1.0） cathode materials were measured by DC four probes, X-ray photo-electron spectrum （XPS） was also introduced to determine the chemical state of Co, F.e ions in LSCF. It is found that the electrical conductivity of each sample has a maximum value with increasing temperature. XPS analysis shows that Co ion has three different chemical states, corresponding to two with Fe ion. The analyses indicates that the small-polaron hopping mechanism dominates the electron conduction at low temperature, while at high temperature, the three factors such as the thermally activated disproportionation of Co^3＋ ions into Co^2＋ and Co^4＋ pairs, the ionic compensation of oxygen vacancies formed at high temperatures, and Fe^4＋ ions charge compensation preferential to Co^4＋, all contribute to electrical conduction.     

Preparation and properties of β-tricalcium phosphate porous bioceramic

Porous β-tricalcium phosphate bioceramic (PTCP) has important roles in surgical implants because of good biocompatibility. But the low compressive strength of the ceramic limits its application. The preparation of PTCP was improved with the adjustment of the constituents and the sintering-process. A new type of PTCP material with high compressive strength was made. The compositions, microstructure and properties of PTCP were analyzed by TG-DSC, XRD, TEM, SEM and so on. The result indicates that stearic acid burns sufficiently and gives out carbon dioxide and water vapor when slowly heated between 200 ℃ and 400 ℃ so that the porous structure like coral in β-TCP bioceramic is formed. Through crystallization at 470 ℃ and 570 ℃, more CaO-P2O5 glass-cement is converted into crystallite-glass, which is beneficial for improving the compressive strength of β-TCP bioceramic.PTCP can form a support action in bone imperfect section with good solubility.     

氟化镧对镍基自润滑合金力学性能及高温摩擦学特性的影响

用粉末冶金热压方法制备了含不同LaF3添加量的Ni-Cr-Mo-Al-Ti-B-MoS2-LaF3系宽温度范围自润滑合金，测试了合金力学性能及与Al2O3陶瓷配副下的高温摩擦磨损性能。研究结果表明，合金的力学性能随LaF3添加量的增加而降低，但其减摩耐磨能力随LaF3添加量的增加而提高。合金中的硫化物（CrxSy,Mo2S3和AlLaS3)是合金低温范围内（室温至300℃）自润滑的主要因素；高温摩擦时（400－700℃）合金表面氧化物和残余硫、镧的化合物及地偶表面转移膜中氧化物与复合氧化物的协同作用是摩擦因数进一步降低的原因。     

XD反应合成Al3Ti,α-Al2O3和TiB2/Al复合材料的界面结构

借助于SEM和TEM研究了Al—TiO2-B2O3系热扩散反应法合成铝基复合材料的界面结构。结果表明：在B2O3与TiO2摩尔比小于1时，增强相由棒状的Al3Ti及颗粒状的TiB2和α-Al2O3组成。Al3Ti与基体的界面干净、相容性好，在基体中分布均匀；TiB2与铝基体界面干净，并存在以下位向关系：[231^-]Al∥[0001]TiB2，（204^-）Al∥（2420^--）TiB2，可成为基体结晶时的核心，细化基体晶粒；口一Al2O3与铝基体的润湿性差，被推挤到基体颗粒的界面呈偏聚状态，并存有孪晶现象，其孪晶面为（111），孪生方向为[112^-]。     

Microstructure of reactive sintered Al bonded Si3N4-SiC ceramics

Aluminium nitride-silicon nitride-silicon carbide （AIN-Si3N4-SiC） composite ceramics were prepared to increase the bending strength and improve the phase structure of Si3N4-based ceramics. The ceramics were made by reactive sintering in N2 atmosphere at 1 360 ℃, using Al as sintering additive. The phase composing of ceramics was identified with an X-ray diffractometer and the microstructure of the materials was studied by scanning electron microscopy. The results indicate that the phase structure is affected remarkably and the interface modality is changed. The interface between Si3N4 and SiC becomes blurry and that between SiC and AlN matches more better at the same time. But the liquid-phase appears during the reactive sintering along with the addition of AI by which the melting point of Si is decreased. The appearance of liquid Si decreases the bending strength of the ceramics. Lower temperature nitrification technic was introduced to avoid the appearance of liquid-phase Si. The optimum addition of Al was investigated by XRD and SEM analysis in order to obtain the maximal bending strength of materials.     

铼酸铁高温润滑行为和配副关系

用化学法合成了Ｆｅ－Ｒｅ合金高温摩擦过程中产生的铼酸铁（Ｆｅ（ＲｅＯ４）３），测定了它的高温摩擦行为。结果表明：在室温至６００℃范围内，铼酸铁有较好的减摩作用，其润滑行为和配副有关，对摩材料的硬质值是否相配、铼酸铁与配副材料的相容性以及盘材表面粗糙度的大小均对它的润滑行为有较大影响。提出了配副原则。     

聚乙烯表面紫外光接枝MPC及其性能研究

将所合成的生物相容性单体2-甲基丙烯酰氧乙基磷酸胆碱(MPC) 通过紫外光接枝到聚乙烯表面,以改善其表面的润滑性、生物相容性以及耐磨性.通过IR、ATR-FTIR、XPS、SEM以及722分光光度计等手段检测了接枝前后聚乙烯样品的相关性能,并研究了接枝前后聚乙烯样品在蒸馏水、生理盐水润滑下的摩擦磨损性能.结果表明,聚乙烯表面可接枝MPC,且接枝量随光照时间的增加而增大;接触角由64°～76°变成15°～26°,接触角大小随接枝量的增大而减小;接枝后样品的溶血率比接枝前低,且样品表面几乎没有血小板;接枝后样品摩擦因数变小,体积磨损率降低.     

氯氧镁水泥浆体水化相及其对强度指标影响初探

本文力图从合成氯氧镁水泥的纯相入手,研究浆体的基本水化相及其相变规律。研究表明,用正确的配比,采用人工合成的方法,可以得到氯氧镁水泥的基本水化相,即5·1·8和3·1·8,并指出了这两种水化相的变化规律。采用不同浓度的MgCl_2溶液配制的氯氧镁水泥浆体,其水化相主要是5·1·8和Mg(OH)_2,采用半定量的计算方法,可以得到这两种水化相之比与浆体强度的对应关系,因而正确选择水化相的比例,可以获得最佳强度的水泥浆体。