MICROSTRUCTURE AND FATIGUE PROPERTIES OF A WELDED DUPLEX STAINLESS STEEL

Abstract— In response to the increasing structural applications in duplex steels for welded structures, fatigue behaviour of a SAF 2304 grade duplex stainless steel was investigated, considering both the base metal and GTAW welded joints. Fatigue curves and fatigue limits under rotary bending fatigue were obtained. The study focused attention on the microstructural features of fatigue crack propagation of the two series of experiments, thereby permitting an evaluation of the tortuous crack path of welded joints and the mechanisms related to threshold microstructural barriers.     

VILOFT织物的染整工艺

新型VILOFT粘胶纤维织物具有独特的扁平截面，导湿透气，蓬松保暖。本文探讨该纤维织物的前处理，染色，整理工艺，优化并给出了具体工艺参数，对实际生产有一定的参考价值。     

Design improvements on rotary valve particle feeders used for obtaining suspended airflows

The back repulsion of low density particles, sticking of particles in feeder valve and interlocking and cohesive archs of particles in feeder hopper have been widely observed problems of a conventional rotary valve feeder used for feeding of granular particles into an airflow line. In this study, these problems of the rotary valve feeders were isolated by means of novel modifications to its conventional design. Results of the modifications showed that the modified feeder can be sensitively used to feed granular particles with mass feeding rates ranging between 5±0.15 and 85±0.85 g/s without encountering problems experienced with conventional rotary valves.     

铁谱分析技术在燃油中非金属杂质监测方面应用的研究

通过对制谱时，谱片上磨屑沉积机理的重新分析，发现非金属磨屑在自身重力的作用下，仍可有规律地沉积在谱片上。据此特点成功地将柴油中的沙砾等杂质有规律地沉积到谱片上，并检测出了某型叉车柴油机喷油泵柱塞断裂的原因。     

Analytical Expression of the Threshold Pump Power of Erbium—doped Fiber Laeers Pumped at 980 nm and 1480nm Wavelengths

The rate equations,which is suiable to erbium-doped fiber lasers pumped at 980 nm and 1480 nm wavelengths respectively,are investigated,and analytical ex-pressions of the threshold pump powers under two pump wavelengths are derived.As a result,some important parmeters can be quantitatively specified.     

环形转底炉海绵铁生产方法

介绍了国内外环形转炉生产海绵铁方法（Ｆａｓｔｍｅｔ法，Ｉｎｍｅｔｃｏ法和ＣＯＦ－Ｒ）发展状况。分析了此种工艺的工艺特点和热工特点，指出了这种方法与回转窑法，遂道窑法比较具有强大的市场竞争力。     

Ultrasonic-assisted drilling of Inconel 738-LC

Generally in the drilling of modern aviation materials such as nickel and titanium base super alloys, problems frequently occur in terms of burr formation at the cutter exit, tool stress, high heat generation on tool surface as well as low process reliability. A recent and promising method to overcome these technological constraints is the use of ultrasonic assistance, where high-frequency and low-amplitude vibrations are superimposed on the movement of cutting tools. This paper presents the design of an ultrasonically vibrated tool holder and the experimental investigation of ultrasonically assisted drilling of Inconel 738-LC. The circularity, cylindricity, surface roughness and hole oversize of the ultrasonically and conventionally drilled workpieces were measured and compared. The obtained results show that the application of ultrasonic vibration can improve the hole quality considerably. Improvements of up to 60% have been achieved.     

耐腐蚀高压柱塞泵用新型双相不锈钢的研究

叙述了新型双相不锈钢－ＷＳＤ钢的组织及其耐蚀性能。试验结果表明，ＷＳＤ钢在氯化物介显示出优异耐蚀性能，其抗点蚀性能远超过Ｃｒ１３，１８－８Ｔｉ，３１６Ｌ等钢种，达到国外Ａｌ－６Ｘ，ＳＡＦ２２０５等钢种的水平。     

铝合金挤压铸造用电磁泵定量浇注技术

为了开发研制铝合金挤压铸造用电磁泵定量浇注控制系统,应用试验研究和数学分析的方法,建立了电磁泵流量计算的数学模型,开发了电磁泵定量浇注控制程序.结果表明,电磁泵定量浇注挤压铸件质量精度达到2%.该项技术在铝合金挤压铸造中的应用能有效提高铸件的品质和质量精度,提高材料的利用率和铸件生产率.     

多风道煤粉燃烧器拢焰罩的长度对窑内煤粉燃烧状况影响的研究

本文运用计算流体力学（CFD）技术，以大型流体工程计算软件CFX4．3为工具，模拟研究了喷煤燃烧器的扰焰罩长度对回转窑内煤粉燃烧过程规律的影响，结果表明，一定长度的扰焰罩有利于加强燃烧器出口附近的湍流混合和煤粉燃烧。