高强度船板钢A36的化学成分设计和控制轧制工艺分析

介绍了铌在高强度船板钢A36中的实际应用,分析了邯钢高强度船板钢A36的微合金化和控制轧制工艺,及其对高强度船板钢性能的影响,提出了优化微合金化和控制轧制工艺的具体措施.     

780MPa级超高层大跨距建筑用抗震宽厚板的研究进展

 建筑用钢板正向高强度、高性能、大型化方向发展,780MPa级高强度抗震钢已应用于超高层大跨距建筑中,高强度钢抗震性能已成为重点解决的课题之一。从性能要求、化学成分设计、生产工艺控制及组织控制方法等方面对国内外开发的780MPa级高强度抗震钢的进行了详细对比和分析,旨在为国内780MPa级高强度抗震建钢的开发提供参考,以满足中国高层建筑用钢的国产化需求。     

高屈服点高强度10MnTiNb冷轧板性能研究

阐述了合金元素在10MnTiNb微合金化高屈服点高强度冷轧板中的作用.通过成分设计,热轧、冷轧工艺控制,对该钢的组织性能进行了研究.     

EH36高强度船体结构用钢的开发

介绍了安钢开发高强度船板EH36的主要工艺路线和技术要求。通过合理的成分、工艺设计及控制,研制出具有优异的综合性能的高强度船板EH36,且成分和性能完全符合船级社认证要求。     

厚规格船板钢DH36的生产实践

厚规格高强度船板钢的生产实践表明,采取适宜的成分与控制轧制和控制冷却工艺设计,可确保高强度船板钢具有良好的综合力学性能;同时,分析了影响高强度船板钢组织、性能的因素,发现适当提高终冷设定温度不会影响细晶强化,且可改善表层过冷组织。     

冷轧包装带用钢性能的研究

研究了低合金高强度结构钢用作冷轧包装带用钢的生产工艺,突出承钢的钒资源特色,提高锰、酸溶铝成分,降低钒成分,采用低碳含量控制,满足低合金高强度结构钢冷轧用打包带的使用性能。对热轧参数以及随后冷却方式进行优化组合,通过对加热温度、轧制温度、轧后冷却速度和卷取温度等进行综合控制,研究提高钢材性能的工艺参数。给出了满足钢材高强度、高韧性、良好冷弯性能、成形性能、焊接性能和较低韧脆转化温度等使用要求的化学成分和轧制工艺参数,目前承钢已进行批量生产。     

宝钢热轧超高强度钢的研究开发

在实验室研究了成分及冷却工艺对高强度低合金钢、复相钢、马氏体钢等热轧超高强度钢组织和性能的影响,并在宝钢1880mm热连轧生产线进行了S700MC和MP1200热轧超高强度钢的工业性试验。相对于以往的高强度热轧产品而言,新开发的热轧超高强度钢采用了“以水代合金”的设计思想,通过经济的成分设计、轧后控制冷却技术的有效利用,不同冷却工艺的控制,可实现用相同的成分获得不同强度等级要求的超高强度热轧钢。     

厚规格船板钢DH36的生产实践

厚规格高强度船板钢的生产实践表明，采取适宜的成分与控制轧制和控制冷却工艺设计，可确保高强度船板钢具有良好的综合力学性能；同时，分析了影响高强度船板钢组织、性能的因素，发现适当提高终冷设定温度不会影响细晶强化，且可改善表层过冷组织。     

高强度调质钢XG960E的开发

介绍了湘钢高强度调质钢板XG960E的开发,包括成分设计原则、生产工艺控制要点、钢板组织形貌、实物性能及焊接性能评定等。XG960E钢板具有高强度、高韧性和良好的焊接性能,是制造大型风机叶轮、高端液压支架推移杆部件和大型汽车起重机主臂的理想材料。     

海底输油管道用(Q345B级钢)无缝钢管试制

总结了采用Q345B级低合金高强度结构钢 ,试制海底输油管线用的无缝钢管的生产工艺 ,分析了化学成份的控制及轧制工艺对钢管性能的影响 ,提出了采用Q345B低合金高强度结构钢 ,可以满足用户对该产品的要求 ,并得到钢中各元素的最合适控制范围以及控制钢管终轧温度对改善钢管的综合性能是有效的途径     

Factors influencing the strength differential of high strength steels

Room temperature tensile and compressive true stress-true strain curves of various high strength steels (quenched and tempered 4340 steel, 410 martensitic stainless steel, and H-11 steel; and aged 300-grade 18 Ni maraging steel) were analyzed to determine the effect of the various microstructures, on what has been termed the strength differential (SD),i.e., the strength level difference between the tensile and compressive flow curves. Care was taken to insure that the compressive deformation was homogeneous. Regardless of the amount of plastic deformation, the quenched and tempered steels exhibited a higher flow stress in homogeneous compressive deformation than for tensile deformation. The extent of the SD was dependent on tempering temperature. This observation is consistent with what others have observed regarding yield strength behavior of quenched and quenched-and-tempered steels. Despite the low carbon content, aged maraging steel also showed a greater resistance to homogeneous compressive deformation. Metallographic examination of the maraging steel revealed the banding that is indicative of segregation. However, homogenization had little effect on the SD despite a change in austenite grain size, reverted austenite content, and the austenite-to-martensite transformational strains shown by Goldberg to be present in segregated material.     

Development of high strength zirconium alloys

Abstract

Assessment of the effects of various alloying elements and strengthening methods in zirconium alloys has indicated that alloys with adequate strengtl1 for use as pressure tube material at temperatures above 400°C can be developed. Ternary, quaternary and quinary alloys based on zirconium have been prepared and subjected to various thermal and deformation treatments. Their age-hardening behaviour and tensile properties are described and some information on their corrosion resistance and response to fast neutron irradiation at 300° and 450°C is presented. The target of UTS in the range 90–120 kpsi at 450°C can be achieved in alloys having an acceptable thermal neutron capture cross section. Adequate strength combined with the ductility necessary for pressure tube fabrication can be obtained by air cooling selected alloys from temperatures high in the (α + β) range.

Résumé

L'evaluation des effets de divers éléments d'alliage et des méthodes dc durcissement permet de croire que des alliagcs ayant une résistance adéquate peuvent être développés pour des tubes de force utilisés à des températures supérieures à 400°C. Des alliages ternaires, quaternaires et quénaires à base de zirconium ont été préparés et soumis à divers cycles thermiques et cycles de déformation. L'étude a porté sur leur vieillissement et leurs propriétés en traction; quelques observations sur leur tenue en corrosion et en irradiation par des neutrons rapides à 300° et 450°C sont présentées. Il est possible d'atteindre des résistances à la traction de 90 à 120 kpsi a 450°C pour des alliages ayant une faible section de capture des neutrons. Une résistance suffisante jointe à la ductilité nécessaire pour la fabrication des tubes peut être obtenue par refroidissement à l'air de certains alliages à partir d'une température élevée dans le domaine α + β.     

纳米高强度复合材料的发展现状

介绍了纳米高强度复合材料制备方法。工艺和强度改善方面的进展。目前陶瓷纳米复合材料、碳纳米管复合材料是人们开发的热点，最后介绍了高强度纳米复合材料的应用前景。     

高强度管线钢板X70的开发

对高强度管线钢的市场需求和国内外发展进行了分析,通过系列技术研究,韶钢开发的高强度管线钢X70实现批量供货．X70强度韧性指标达到西气东输二线要求．     

Gaseous hydrogen embrittlement of high strength steels

The kinetics of sustained-load subcritical crack growth in hydrogen were determined for 18Ni(200) and 18Ni(250) maraging steels over a range of hydrogen pressures and temperatures. Crack growth in each steel was characterized by an apparent threshold stress intensity, a domain where the growth rate increased sharply with stress intensity (K) (Stage I), and a range where the growth rate was independent ofK (Stage II). The rate-limited Stage II crack growth in these steels exhibited three distinct regions of temperature dependency, with a different isothermal pressure dependence in each region. In the low temperature region, Stage II crack growth was thermally activated with δH = 18.2 ±1.7 kj/mol; (δH being independent of hydrogen pressure and yield strength). The growth rates at a givenK were proportional to the square root of hydrogen pressure. In the intermediate temperature region, Stage II growth rates increased at slower rates, passed through a maximum and then decreased with increasing temperature. Within this region, the pressure dependence for crack growth increased from 1/2-power to 2.0-power with increasing temperature. Above a transition temperature, each grade of maraging steel became essentially immune to gaseous hydrogen embrittlement for the hydrogen pressure range considered. The transition temperature was strongly affected by yield strength and hydrogen pressure. Plausible explanations for these phenomenological results are considered. Formerly a graduate student in the Department of Metallurgy and Materials Science, Lehigh University     

Development of high strength wrought aluminum-base alloys

Work is reported on small-scale laboratory techniques described for development of high strength wrought aluminum alloys and on structure and properties of alloys produced. Alloy screening tests were on splat cooled samples and mechanical property measurements were from cast and rolled thin section cast plates. The highest tensile strengths obtained were in excess of 115,000 psi; highest yield strenghts were in excess of 110,000 psi. Four different alloys tested showed yield strengths in excess of 90,000 psi with elongations in excess of 5 pct.     

Room temperature creep of high strength steels

The room-temperature creep behaviour of three high strength steels has been investigated. Several parameters such as creep stress, loading rate, stress history and heat treatment has been altered and their influence on the low temperature creep has been reported. The primary creep in all three alloys agreed well with the logarithmic creep law and the creep mechanism has been identified as pure dislocation creep. Higher stresses and high loading rates led to increased creep strains and strain rates. Reloading after a period of creep resulted in significantly decreased creep strains and no recovery of the time dependent deformation could be detected. The yield strength of the materials per se had no influence on the room temperature creep whereas the same material with decreased 0.2% offset strength showed significantly reduced time dependent deformation. The possible interaction between primary creep and stress corrosion cracking has been discussed.     

Recent developments of the high strength and high ductility nanostructured materials

This talk will summarize the recent work related to a kind of new nanomaterials produced by the SMAT (surface mechanical attrition treatment).The concept of surface nanocrystallization of materials will be presented.In terms of the grain refinement mechanism induced by plastic deformation,a novel surface mechanical attrition(SMA) technique was developed for synthesizing a nanostructured surface layer on metallic materials in order to upgrade the overall properties and performance.The grain refinement mechanism of the surface layer during the SMA treatment will be analyzed in terms of the nanostructure observations in several typical materials.Very high yield stress(5 times of the base material) on the surface layer of the material obtained by the SMAT has been observed.The effect of surface nanostructures on the mechanical behavior and on the failure mechanism of metallic material shows the possibility to develop a new strength gradient composite using co-rolling and nitriding.The role of residual stress induced during the treatment will be investigated and discussed.The developed materials are also porosity free materials which can be used as reference material for the local mechanical behavior investigation technique such as the nanoindentation.A general concept for obtaining high strength and high ductility nanostructured materials will be presented.The exceptional high strength and high ductility steels have developed.The simulation of the mechanisms for improving ductility of high strength nanostructured materials will be presented.The potential applications for the land transportation vehicles(car,bus,train) and wind energy have been investigated.Some examples of concept design for the integration of the advanced nanostructured steels will be presented.     

Creep and stress-rupture of high strength zirconium alloys

Abstract

Zirconium-based alloys with small additions of tin, molybdenum, niobium and aluminum are being developed as candidate materials for high-strength pressure tubes in advanced CANDU reactors. The out-reactor creep and stress-rupture properties of 12 alloys based on these elements have been determined and correlated with their metallographic structures and substructures and thermomechanical histories. An alloy of composition Zr-3 wt% Sn-1 wt% Mo-1 wt% Nb was the best for high creep strength, low neutron capture cross section and reasonable corrosion resistance.

Résumé

Des alliages à base de zirconium et con tenant de faibles additions d'étain, de molybdéne, de niobium et d'aluminium sont en voie de développement comme matériaux à haute résistance pour des tubes de force pour le réacteur CANDU. Les propriétés de 12 de ces alliages ont été évaluées hors réacteur quant au fluage et à la rupture; des corrélations ont été établies entre ces propriétés et la structure métallographique, et les traitements thermomécaniques subis. Le meilleur alliage pour sa résistance au fluage, sa faible section de caputre des neutrons et sa résistance à la corrosion, a une composition de: Zr-3% Sn-1% Nb (% pondéral).