漫射红外技术的智能家居无线局域网设计

分析了红外技术在短距离无线通信中的优势,并将其应用在智能家居局域网中;结合安华高科技公司的HSDL-3020红外收发模块搭建了硬件电路,构成网络的主从节点;介绍了网络组建的过程,包括IrDA协议栈结构、数据编码格式、链路连接、网络管理机制等。本设计实现了对家居设备的统一管理,具有较高的应用价值。     

展望UNS的新型智能终端

文章主要根据国内外终端生产现状,根据未来无处不在的网络社会(UNS)的要求给出了未来新型智能终端的设计思路、分类、特点及其典型应用,展望了新型终端应用的美好前景。     

溶胶凝胶法制备燃料电池金属双极板抗氧化导电涂层

通过溶胶凝胶法在铁铬合金表面制备La1-xCaxCrO3涂层以改善其高温抗氧化性能.采用红外光谱(IR)测定溶胶所含官能团,用差热分析(DTA)、热重法(TG)、X射线衍射法(XRD)分析涂层的相变规律,并用扫描电镜(SEM)等观察涂层结构和对比氧化腐蚀的表面形貌.结果表明,通过溶胶-凝胶法在铁铬合金表面形成的均匀涂层能有效防止氧化行为发生,并具有良好的电导率,是高温下对金属双极板有效的保护方法.     

Mechanisms of erosion-corrosion on a cobalt-base alloy and stainless-steel UNS S17400 in aggressive slurries

Two materials, which are candidates in the construction of drill bits, have been studied in severe liquid-solid impingement conditions. Analysis of the weight loss was carried out on Stellite X40 (Co-base) and UNS S17400 (stainless steel) materials at 30, 60, and 90° angles of impingement under erosion-corrosion conditions at the free-corrosion potential and with applied cathodic protection. A preliminary analysis of the corrosion behavior of the materials in static conditions was the starting point for the electrochemical analysis. A more extensive corrosion analysis under erosion-corrosion conditions was carried out through direct current (DC) potentiodynamic tests with varying angles of impingement. The results were used to identify the contribution of mechanical erosion and electrochemical corrosion for both materials under different angles of impingement and to determine the extent of interaction between corrosion and mechanical-erosion processes.     

固溶温度对UNS N07718合金组织及冲击性能的影响

研究了固溶处理对固溶-时效UNS N07718合金[/%:0.03C, 52.50Ni, 18.0Cr, 3.0Mo, 5.0(Nb+Ta), 0.90Ti, 0.50Al]显微组织及冲击性能的影响。960℃+时效处理后,针状δ相弥散分布于晶内和晶界,晶粒尺寸均匀细小,冲击功17 J;1 000℃+960℃+时效处理后,δ相尺寸增大呈针片状分布于晶界处,数量减少,晶粒尺寸增大;1 010℃+960℃+时效处理后,δ相由针状转变为颗粒状,断续分布于晶界,晶粒明显长大;1 020℃+960℃+时效处理后,颗粒状δ相全部溶解。1 010℃+ 960℃+时效处理后,样品冲击功为43 J,相较于960℃+时效,冲击功提升150%,且冲击断口呈现明显的韧窝结构。     

铁镍基耐蚀合金凝固组织控制研究

采用固定式电渣重熔工艺、单电极导电结晶器抽锭电渣重熔工艺和双极串联抽锭电渣重熔工艺以不同的熔化速度生产出UNS N08825合金电渣锭,分析了电渣锭的结晶组织、热加工性能以及三种冶炼工艺的电极熔化速度、冷却条件和温度场差别。结果表明,当UNS N08825合金电渣锭凝固组织的柱状晶方向与纵轴方向夹角θ不大于54°时,钢锭具有良好的热加工塑性。     

Effect of different microstructural features on the hydrogen embrittlement susceptibility of alloy 718

Due to its high strength and acceptable corrosion resistance, Alloy 718 is a viable material for the use in subsea applications. The alloy's susceptibility to hydrogen embrittlement is however limiting its viability. In this work the effect of microstructure on the hydrogen embrittlement susceptibility of Alloy 718 was examined by the use of slow strain rate testing on three different heat treatments. Cathodic pre-charging and polarization during testing were used to introduce hydrogen into the samples. A severe reduction in the ductility of the alloy due to the precipitation phases γ″ and γ′ were found. In addition, one of the heats had a continuous film of a Nb and C rich phase on the grain boundary giving an intergranular fracture mechanism. This intergranular fracture mode was further enhanced by the presence of hydrogen. In the solution annealed condition, the presence of hydrogen reduced the dimple size on the fracture surface.     

The effect of surface modification on the corrosion protection ability of the passive films of sensitized UNS S31803 duplex stainless steel

ABSTRACT

The influence of sensitisation heat treatment, surface roughness and repetitive cyclic voltammetry (RCV) procedure (that was used to create passive films on the surface of sensitised samples) on the corrosion behaviour of UNS S31803 duplex stainless steel was evaluated using sodium hydroxide etching, double-loop electrochemical potentiodynamic reactivation (DLEPR), potentiodynamic polarisation, Mott–Schottky analysis, X-ray diffraction and optical microscopy techniques. The results showed that prolonged sensitisation time leads to the formation of defective passive films on the surface. In addition, as the substrate surface roughness decreases, the defect concentration in the resulting passive film decreases. Moreover, thick passive films that were created at a high number of RCV cycles contain fewer defects than the thin ones. Finally, the specimens with smooth surfaces, thick passive films and low degree of sensitisation exhibit high corrosion resistance due to their intact passive layers formed on their surfaces.     

热交换器用镍基合金UNSN06600无缝管生产工艺研究

简述了热交换器用镍基合金UNSN06600无缝管的基本性能、制造技术特点以及开发UNSN06600无缝管生产工艺的过程,最后确定了采用“斜轧热穿孔开坯＋全冷轧”生产工艺。通过对成品管进行力学性能检测和微观组织分析可知,采用该工艺生产的镍基合金UNSN06600钢管满足ASMESB163标准的要求。     

超级13Cr与镍基合金UNS N08028钝化膜耐蚀性研究

通过极化曲线和Mott-Schottky曲线,研究了超级13Cr和镍基合金UNS N08028分别在100℃、130℃和150℃且含CO_2和Cl~-的腐蚀介质中浸泡7天所形成钝化膜的电化学行为和半导体性质。极化曲线表明,超级13Cr在100℃时形成的钝化膜具有良好的耐蚀性,而镍基合金UNS N08028在150℃时形成的钝化膜耐蚀性更好。产生这种现象的原因和表面钝化膜的半导体性能密切相关,二者在100℃时形成的钝化膜均具有双极性n-p型半导体特征,但超级13Cr表面钝化膜的掺杂浓度相对于镍基合金UNS N08028较小;而在150℃介质中,超级13Cr形成的钝化膜转变为p型半导体,镍基合金UNS N08028仍然保持着双极性n-p型半导体特征。故在较低的温度和CO_2分压下,超级13Cr表面钝化膜的耐蚀性较好。而在较高的温度和CO_2分压下,UNS N08028表面钝化膜对基体的保护性反而更好。