Fracture toughness of alloy 690 and EN52 welds in air and water

The effect of low- and high-temperature water with high hydrogen on the fracture toughness of alloy 690 and its weld, EN52, was characterized using elastic-plastic J _IC methodology. While both materials display excellent fracture resistance in air and elevated-temperature (>93 °C) water, a dramatic degradation in toughness is observed in 54 °C water. The loss of toughness is associated with a hydrogen-induced intergranular cracking mechanism, where hydrogen is picked up from the water. Comparison of the cracking behavior in low-temperature water with that for hydrogen-precharged specimens tested in air indicates that the critical local hydrogen content required to cause low-temperature embrittlement is on the order of 120 to 160 ppm. Loading-rate studies show that cracking resistance is improved at rates above ∼ 1000 MPa √m/h, because there is insufficient time to produce grain-boundary embrittlement. Electron fractographic examinations were performed to correlate cracking behavior with microstructural features and operative fracture mechanisms.     

钢铁企业技术进步评价的探讨

根据近年来钢铁企业技术进步评价的经验并参考了国内关于科技进步评价的一些科研成果，结合钢铁工业生产的实际情况，提出钢铁行业技术进步评价的方案。     

Fracture toughness of alloy 600 and an EN82H weld in air and water

The fracture toughness of alloy 600 and its weld, EN82H, was characterized in 54 °C to 338 °C air and hydrogenated water. Elastic-plastic J _IC testing was performed due to the inherent high toughness of these materials. Alloy 600 exhibited excellent fracture toughness under all test conditions. While EN82H welds displayed excellent toughness in air and high-temperature water, a dramatic toughness degradation occurred in water at temperatures below 149 °C. Comparison of the cracking response in low-temperature water with that for hydrogen-precharged specimens tested in air demonstrated that the loss in toughness is due to a hydrogen-induced intergranular cracking mechanism. At loading rates above ∼1000 MPa , the toughness in low-temperature water is improved because there is insufficient time for hydrogen to embrittle grain boundaries. Electron fractographic examinations were performed to correlate macroscopic properties with key microstructural features and operative fracture mechanisms.     

欧洲标准EN10083-2:1996非合金钢交货技术条件简述

由欧共体各国制定一批重要的欧洲标准,各国采用双编号方式以等同方法制定成员国标准.现作系列简述,以便参考.     

EN10083-1:1996特殊钢交货技术条件

详细介绍、分析及对比了EN10 0 83- 1:1996特殊钢交货技术条件的适用范围、订货资料、牌号与化学成分、力学与工艺性能、其它要求以及表面质量规定 ,对特殊钢的生产贸易应用有一定借鉴作用     

Effects of Burnishing Parameters on the Surface Characteristics,Microstructure and Microhardness in EN Series Steels

Surface finish and surface hardness of the components play vital role in quality of products/components, in general and failure resistance, in particular. One of the finishing process involving surface plastic deformation that introduces compressive residual stresses and thereby improves fatigue resistance is “Burnishing”. Even though the burnishing process is widely employed, its process parameters were not systematically studied till date and not fully established for various important structural materials. The burnishing process parameters include force, speed, feed, and number of tool passes. In the present study, the data obtained from systematically conducted burnishing experiments are correlated with theoretical design using Taguchi method in case of EN series steels (EN 8, EN 24 and EN 31). The surface characterization employed includes optical microscopy, microhardness and magnitude of residual stress. The study revealed a one-to-one correlation between burnishing depth, increase in average microhardness and magnitude of compressive residual stresses and a peak in all these three at intermittent extent of burnishing (either after first or second pass) in all the three alloy steels.     

Prediction of Surface Roughness in Turning of EN 353 Using Response Surface Methodology

In the present work, an attempt has been made to investigate the influence of cutting speed, feed, depth of cut and nose radius on surface roughness during wet turning of EN 353 steel using tungsten carbide inserts. Surface roughness prediction models in terms of speed, feed, depth of cut and nose radius is developed by using response surface methodology based on center composite rotatable design. A comparison of first order models with quadratic model was carried out on the basis of percentage mean absolute error and mean square error. The results clearly reveals that the predicted data using quadratic model is in close agreement to the experimental surface roughness values as compared to predicted data using first order model. In addition to this, it has been revealed that the speed is the main influencing factor affecting the surface roughness. The depth of cut has no significant influence on the roughness. Mathematical model for surface roughness shows that surface roughness decreases with increase in speed and nose radius, but increases with increase in feed. The percentage variation between the predicted and experimental values of the surface roughness during the confirmation experiments was found within 5 %. An attempt has also been made to obtain optimum cutting conditions for minimum surface roughness.     

推进科技进步 促进企业节能降耗

文章介绍了山东铝业公司采用先进改造原有工艺和设备及所取得的节能降耗效果，对同行业企业有一定的参考作用。     

Staurosporine induces neurite outgrowth in neuronal hybrids (PC12EN) lacking NGF receptors

A novel neuronal model (PC12EN cells), obtained by somatic hybridization of rat adrenal medullary pheochromocytoma (PC12) and bovine adrenal medullary endothelial (BAME) cells, was developed. PC12EN cells maintained numerous neuronal characteristics: they expressed neuronal glycolipid conjugates, synthesized and secreted catecholamines, and responded to differentiative agents with neurite outgrowth. PC12EN lacked receptors for EGF and both the p75 and trk NGF receptors, while FGF receptor expression was maintained. Staurosporine (5-50 nM), but not other members of the K252a family of protein kinase inhibitors, rapidly induced neurite outgrowth in PC12EN, as also found in the parental PC12 cells, but not in BAME cells. Similarly, both acidic and basic FGF (1-100 ng/ml) were neurotropic in PC12EN. In contrast to the mechanism by which FGF promoted neurite outgrowth in PC12EN, the neurotropic effect of staurosporine did not involve activation of established signalling pathways, such as tyrosine phosphorylation of erk (ras pathway) or SNT (a specific target of neuronal differentiation). In addition, staurosporine induced the tyrosine phosphorylation of the focal adhesion kinase p125FAK. However, since the latter effect was also observed with other protein kinase inhibitors of the K252a family, which induced PC12EN cells flattening but no neurite extension, we propose that FAK tyrosine phosphorylation may be related to ubiquitous changes in cell shape. We anticipate that PC12EN neuronal hybrids will become useful models in neuroscience research for evaluating unique cellular signalling mechanisms of novel neurotropic compounds.     

Magnetron Sputtered TiN Coatings Modified by Chromium,Nickel and Electroless Nickel (EN) Interlayers on Mild Steel

TiN films were deposited by reactive d.c. magnetron sputtering on mild steel substrate. Because of presence of inherent porosity and internal stresses, TiN coatings cannot be relied to give corrosion protection; also TiN coatings need a good load support. Electroplated chromium and nickel and electroless nickel (EN) were deposited by plating as interlayers below the TiN coatings to study comparatively the effect of these interlayers. Chromium was electrodeposited from conventional sulfate catalysed chromic acid bath and nickel using Watt's bath while EN by electroless deposition process using acidic hypophosphite bath. Three different thicknesses viz. 2, 4 and 10 μm of interlayers were employed to study their influence on TiN coatings. The corrosion behaviour of TiN coated mild steel samples with and without the interlayers was studied using potentiodynamic measurement technique in deaerated IN H₂SO₄ electrolyte. It was observed that TiN coatings on mild steel without any interlayer almost mimic the behaviour of the substrate, while the presence of any of the three interlayers showed a considerable improvement in the corrosion resistance.     

Magnetron Sputtered TiN Coatings Modified by Chromium,Nickel and Electroless Nickel (EN) Interlayers on Mild Steel

Abstract

TiN films were deposited by reactive d.c. magnetron sputtering on mild steel substrate. Because of presence of inherent porosity and internal stresses, TiN coatings cannot be relied to give corrosion protection; also TiN coatings need a good load support. Electroplated chromium and nickel and electroless nickel (EN) were deposited by plating as interlayers below the TiN coatings to study comparatively the effect of these interlayers. Chromium was electrodeposited from conventional sulfate catalysed chromic acid bath and nickel using Watt's bath while EN by electroless deposition process using acidic hypophosphite bath. Three different thicknesses viz. 2. 4 and 10 μm of interlayers were employed to study their influence on TiN coatings. The corrosion behaviour of TiN coated mild steel samples with and without the interlayers was studied using potemiodynamic measurement technique in deaerated IN H₂SO₄ electrolyte. It was observed that TiN coatings on mild steel without any interlayer almost mimic the behaviour of the substrate, while the presence of any of the three interlayers showed a considerable improvement in the corrosion resistance.

Microhardness measurements have shown that the surface hardness values of TiN coatings on mild steel increased to 1907 HK₂₅ from about 1000 HK₂₅ when employed with chromium interlayer. and to 1484 HK₂₅ with EN interlayer, while electroplated nickel as an interlayer increased the hardness to a lesser extent (1289 HK₂₅).

X-ray diffraction analysis has shown that the phases present in the TiN coatings were mainly TiN (200) and TiN (111). Chromium coated samples were found to show the broadening of Fe (110) peak, which also corresponds to Cr (110) peak. Interlayer nickel showed the presence of mainly Ni (200) and Ni (111) phases while EN was amorphous in structure. The crystalline phases Ni₃P and Ni were evident when TiN top-coat was given by d.c. magnetron sputtering on EN plated mild steel samples.     

欧洲标准EN10083-3(1996)硼钢交货技术条件标准综述

介绍了欧洲基础标准中的硼钢交货技术条件标准,该标准针对硼钢特点,为满足结构件的要求作了详细规定,具有一定参考与使用价值.     

吉恩镍业公司奥转炉烟气制酸试生产问题研究

简述吉镍烟气制酸系统试生产中存在的问题,并提出解决问题的主要措施.     

材料科学技术转型发展与钢铁创新基础设施的建设

摘要：在第4次工业革命浪潮的推动下,钢铁科学与技术正在经历数字化、智能化转型。钢铁行业全流程各工序均为“黑箱”,为多场、多相、多变的巨系统,具有复杂相关关系和遗传效应等。这些不确定性带来了巨大的挑战。挑战和机遇并存。这些不确定性提供了智能化和数字化技术的应用场景资源;钢铁行业极为丰富的大数据提供了挖掘其中蕴含客观规律的数据资源;现代的数据科学、智能技术为解决不确定性问题提供了强大的手段。以数据为中心,以工业互联网为载体,以实验工具、数字数据、计算工具为支撑,建设钢铁企业材料创新基础设施,将可以大幅度提高研发效率,降低研发成本,有力地支撑钢铁材料科学与技术的转型发展。实验工具平台除了传统的实验室仪器装备和中试装备之外,实际生产线被作为主要的实验工具。这些实验工具提供丰富、精准、写实的历史数据和现实生产数据,特别是生产线装备提供实际生产大数据,蕴含着生产过程中的全部规律,是极宝贵的数据资源。利用机器学习、深度学习等现代数据挖掘技术为计算工具,对这些数据资源进行处理、分析、计算,将数据转换为高保真度模型,可以得到具有“原位分析能力”的数字孪生。在工业互联网的总体架构下,以数字孪生为核心,组成信息物理系统,构建起基于数据自动流动的状态感知、实时分析、科学决策、精准执行的闭环赋能体系,解决生产制造、应用服务过程中的复杂性和不确定性问题,提高资源配置效率,实现资源优化,对材料行业转型发展提供关键技术支撑。虚实映射、实时交互、精准控制的信息物理系统与材料创新基础设施合二为一,以材料创新基础设施为基盘,形成具有“原位分析能力”的数字孪生,建设钢铁生产全流程、一体化的信息物理系统,必将推进钢铁行业智能制造蓬勃开展和数字化、智能化转型。     

Praise and Blame and Robinson.

Daniel Robinson suggests that much of the civil and criminal law "serves as the institutionalized form of praise and blame". Indeed it does. Pulling at this thread of Robinson's tapestry leads the reader straightaway to a host of truths about how law and morality not only intersect, but work together in harmony. "[L]aw", Robinson says, is a "vivid expression of deeper and impenetrably complex moral theories". This essay explores several of these harmonies, but focuses on two. One is that political society must be seen as the cooperation of free persons according to law, which persons hold common moral understandings. The second has to do with retribution as the moral justifying aim of punishing criminals. The author goes beyond Robinson's limited praise of retribution, and shows that some central features of our practice of punishment are understandable only within the retributive framework. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

深云立交桥梁检测及加固改造

根据深云立交桥梁的检测结果，对该桥目前的整体状况、工作状态，及其使用情况做出综合评价，对桥的病害原因进行了分析，并提出合理的加固方案。