“七五”期间压力容器用低合金钢的研制动态

最近,我国对“七五”期间低合金用钢科技攻关课题召开了论证会。结果确定13个专项课题列为“七五”低合金钢科技攻关项目,上报国家科委审批。其中,与压力容器有关的有3项,现简介如下: 1.镍系低温用钢的研制专项课题本课题由太钢、鞍钢、北京钢研院和通用所等单位承担,主要针对城市煤加压气化、年产三十万吨乙烯等工程中低温压力容器设备国产化的需要,开展1.5Ni、3.5Ni钢及球罐用低温高强度钢的研制。同时,也对5Ni、9Ni钢开     

09MnNiDR钢板及其焊接接头的低温韧性试验研究

根据低温压力容器用钢的特点,用夏比(V型缺口)冲击,落锤(NDTT)和COD等试验方法,对国内研制的09MnNiDR(含O.5Ni)钢板及其焊接接头进行了系统的试验研究,结果表明:低温韧性优良,—70℃A_(kv)值与国外标准相比裕量很大,是—40～—70℃范围内理想的低温压力容器用钢。     

12Ni14低温钢MAG焊接

某公司生产的缠绕管式换热器，为大型氮肥装置国产化技改项目，根据合同及技术条件要求，其主体材料均采用从欧洲进口的低温钢12Ni14。根据欧洲标准规定，该含镍型低合金钢允许用于低温压力容器制造。根据国外的生产经验，我们对低温钢12Ni14进行了材料试验及验证工作。在此基础上又进行了多项此类型低温钢的焊接工艺试验及工艺评定工作，并成功地应用于缠绕管式换热器的生产制造。     

低温压力容器用钢及其焊接与检测

主要介绍低温压力容器制造用钢及其焊接特点和检测要求,其中对低温钢的焊接特点以及低温钢压力容器制造的特殊检验要求进行了重点介绍。     

-50 ℃用15MnNiNbDR钢板的开发和试验研究

研究了15MnNiNbDR钢正火及SR状态的综合力学性能，研究结果表明，15MnNiNbDR钢具有良好的低温韧性，作为-50℃级正火型低温压力容器用钢是可行的。     

压力容器用钢锻件标准介绍(二)——JB4727—93《低温压力容器用碳素钢和低合金钢锻件》

随着低温压力容器的应用范围日益扩大,低温压力容器用钢锻件也正在逐步走向专门化。美国有SA350《要求缺口韧性试验的管道元件用碳素钢和低合金钢锻件》、SA522《低温用锻制或轧制含8%及9%镍合金钢法兰、管件阀门及零件》和SA765《压力容器元件用要求一定韧性的碳素钢和低合金钢锻件》等专用标准。日本有JISG3205《低温压力容器用碳素钢和低合金钢锻件》专用标准。英国在BS1503《承压用钢的锻制品(含锻制半成品)》中用专门的条款对低温用钢锻件提出特殊要求。国际标准ISO 2604/I《承压钢材—技术要求第一部分·锻件》也用专门章节对低温压力容器用钢锻     

中冶建研低温钢用焊条填补国内空白

中国中冶所属中冶建筑研究总院有限公司“-70℃低温钢用焊条W707Ni的研制”通过成果鉴定。低温钢用焊条是低温设备、低温储罐领域用主要焊材品种之一，也是焊接材料领域的高端产品。为了改变长期以来我国该类焊条过度依赖进口的状况，中冶建研经过两年多的技术攻坚，完成了-70℃低温钢用焊条W707Ni的研制。     

压力容器铁素体钢板

本文考虑了随着在压力容器制造中使用碳钢、微量合金钢及铁素体合金钢而出现的主要发展情况及问题;炼钢实践的改变大大地影响了这些钢的质量。简单地介绍了有关碳钢及碳锰钢的高温强度及低温缺口韧性的工作;对微量合金钢的发展及其设计原理,并结合其成型及焊接的困难,作了讨论;在低合金钢类中举出二个特例,即核能用钢板A533 B类1级钢及石油化工厚壁压力容器用钢2(1/4)Cr-1Mo钢,讨论了它们的制造及使用问题,简单地阐述了低温用9％Ni钢;最后在附录中给出高要求使用的钢板的确认程序。     

0.5Ni低温用钢的研制

本文介绍了武钢近年来与国内有关单位合作研制的-40～-70℃低温压力容器用09MnNiDR(0.5%Ni)钢的综合性能,并就其主要力学性能、显微组织与西德同类钢板作了对比试验研究与分析,结果表明:国产0.5Ni 钢达到了西德 DIN-17280-85标准的要求,具有优良的低温韧性,其实板性能水平亦与西德13MnNi63钢板相当。     

低温钢制压力容器焊接工艺综述

低温钢压力容器是在一定的低温环境下易于发生低应力脆性破坏的压力容器。随着市场经济的改善,我国低温钢压力容器焊接工艺也在不断进步发展,推动了新时代下我国工业生产活动的顺利进行。本文主要通过分析影响低温钢压力容器焊接质量的因素,总结在低温钢制压力容器焊接过程中的相关注意事项和质量控制措施,希望能为未来低温钢压力容器产品市场的发展奠定坚实的基础。     

核电压力容器用钢的发展及研究现状

介绍了核反应堆压力容器用钢的发展和演化规律,给出了常见的各类合金元素在钢中的作用及各类杂质元素的危害,分析了不同热处理工艺、制造工艺对材料性能的影响,最后预测了当前核电压力容器用钢的发展趋势。     

低温压力容器用不锈钢(二)

讨论了各种低温下不同类型的压力容器构件所用奥氏体不锈钢的类型、牌号、性能及其检验。评述了奥氏体不锈钢中的奥氏体相转变为马氏体相的机制和主要影响因素,应对某些技术问题进行研究。     

低温压力容器用不锈钢(一)

讨论了各种低温下不同类型的压力容器构件所用奥氏体不锈钢的类型、牌号、性能及其检验。评述了奥氏体不锈钢中的奥氏体相转变为马氏体相的机制和主要影响因素,应对某些技术问题进行研究。     

油气分离器罐低温环境下应力分析

目前市场上的大部分油气分离器罐设计温度范围是-20～150℃,有少部分油气分离器罐在寒冷地区使用,其环境温度已经低于设计温度.利用ANSYS有限元分析软件进行模拟实际工况,系统的论证分析常规油气分离器罐不必按照低温压力容器去选型设计.当壳体或受压元件使用在“低温低应力工况”下,若其设计温度加50℃后高于-20℃时,不必遵循低温压力容器规定.这样可以大大降低压力容器的使用环境温度,提高整个空压机产品的使用范围.     

基于材料力学性能的最低设计金属温度曲线分析

铁素体钢在低温条件下存在明显的韧脆转变现象。为防止脆断事故的发生,需要确定铁素体钢制压力容器的最低使用温度。针对ASME中的A^D四条冲击豁免曲线,对应地选取了4种材料,基于材料实际的屈服强度和参考温度,按照ASME中豁免曲线的计算方法,计算得到4种材料的最低设计金属温度曲线,并与对应的A^D曲线对比,定量地分析ASME中豁免曲线的保守性。结果表明,ASME中的豁免曲线相对于材料自身的最低设计金属温度曲线保守性较大;韧性相近的材料被划分到不同的豁免曲线,使得韧性富裕量差异较大,对于某些材料,其断裂韧性被低估。     

Friction and wear behaviour of sintered steels submitted to sliding and abrasion tests

Fe–C–Mo and Fe–C–Cr steels were sintered by PM processes carried out using different values of temperature and pressure, leading to different microstructures and density values. Flat specimens were submitted to tribological tests in order to evaluate their behaviour under both dry sliding and abrasive wear conditions. A flat-on-cylinder tribometer was used for the sliding tests, while a micro-scale ball cratering device was used for the abrasion tests. The dry sliding wear resistance of the PM steels was mainly influenced by the composition and sintering conditions. In this regard, the best behavior was observed for the more hardenable Fe–C–Mo steels with higher Mo content, sintered under conditions giving rise to bainitic microstructures. A determining role was also played by the porosity content and pore shape: reduction in porosity (obtained by increasing the sintering temperature and the compacting pressure), as well as an increase in pore roundness, led to a significant improvement in the resistance to sliding wear. A mild oxidative wear regime were observed for all the sintered steels under relatively low values of the applied load, while an increase of the applied load led to a delamination wear regime. The resistance to abrasive wear was low for all the tested steels, irrespective of composition and sintering cycle.     

A comparison of the structure of solute clusters formed during thermal ageing and irradiation

Nanometre scale clusters form in Cu-containing reactor pressure vessel (RPV) steels during neutron irradiation. These clusters have a deleterious effect on mechanical properties, which can result in embrittlement and limit the reactor operating life. Thermal ageing of RPV steels can also induce the formation of solute clusters but it is not clear how similar these are to those formed during irradiation. In this work atom probe tomography, combined with detailed structural assessments of the structure of solute clusters, is used to address this issue.A series of thermal ageing heat treatments has been performed on several high- and low-Ni RPV welds to produce 1-4 nm diameter solute clusters. The same materials have also been neutron irradiated.The results show that CuMnNiSi enriched clusters formed during thermal ageing have, on average, higher Cu contents and lower Mn, Ni and Si contents than those found in irradiation-induced clusters. The effect of increasing bulk Ni is to encourage the formation of clusters with significantly higher Ni content, slightly higher Mn and Si contents and significantly lower Cu contents. At very high doses and dose rates MnNiSi enriched clusters can form even in high-Cu welds.Despite differences in the compositions of individual clusters formed during irradiation and during thermal ageing, clusters in both exhibit similar structure. In particular, well developed clusters in both materials have Cu-enriched cores whose peripheries are enriched in Ni, Mn and, in most cases, Si.     

国内外关于低温压力容器设计理念的比较

通过对GB 150《压力容器》与ASMEⅧ-1以及EN 13445关于低温压力容器设计理念的对比,指出应用GB 150《压力容器》进行低温压力容器设计时应引起注意的地方。同时提出我国低温压力容器标准今后发展的基本思路。     

Atom probe tomography analysis of nanostructure evolution in Ni-Cr-Mo low alloy steel under neutron irradiation

Ni-Cr-Mo low alloy steels are being considered as alternative materials to replace the Mn-Mo-Ni low alloy steels used in reactor pressure vessels in nuclear power plants, because of their higher strength and toughness. However, the neutron irradiation occurring during reactor operation causes degradation of Ni-Cr-Mo low alloy steel. In this study, irradiation-induced clusters in a Ni-Cr-Mo model alloy irradiated in the High-flux advanced neutron application reactor (HANARO) research reactor were investigated via Atom probe tomography (APT). The irradiated specimens showed irradiation-induced hardening and embrittlement. The neutron irradiation caused Si clustering, and these spherical clusters were homogeneously distributed within the matrix. Ni was also clustered at the Si clusters. However, the other elements did not clearly exhibit clustering behavior. Si and Ni atoms were also located at the dislocations. To quantify the nano-sized clusters, a method based on the Density-based spatial clustering of applications with noise (DBSCAN) algorithm was implemented. The total number of clusters was calculated to be ~7 × 10^-4 n/nm³ and the average cluster radius was less than 2 nm. The APT approach was demonstrated to be well suited for discovering the irradiation defect structures.     

超超临界电站锅炉关键材料的新进展

高温材料和性能是制约超超临界(电站)机组发展的关键。讨论了超超临界机组锅炉用铁素体钢、奥氏体钢与镍基合金三类材料的合金化和主要性能,指出随着机组参数的提高,材料的抗蒸汽氧化性能和抗烟气腐蚀性能愈加重要,从而促进了新型奥氏体热强钢和镍基合金的发展;指出了随着超超临界技术的采用,还需要对相关材料进行大量基础试验,特别是长期试验,以积累相关数据和经验。