钢板化学成分对L485M/L555M焊管热影响区性能的影响

统计新气、鄂安沧以及X管线项目所用L555M/X80M和L485M/X70M大直径直缝埋弧焊管的理化试验数据,对比分析钢板化学成分和焊管焊接接头硬度、抗拉强度、导向弯曲试验数据。分析结果表明:钢板化学成分优化后的新气管线项目用直缝埋弧焊管焊接接头热影响区没有出现软化、弱化现象,导向弯曲性能优异,焊管热影响区性能得到明显改善;鄂安沧管线项目用直缝埋弧焊管焊接接头热影响区没有出现软化现象,但出现了一定程度的弱化现象,导向弯曲性能较好,焊管热影响区性能得到改善。     

X80管线钢螺旋埋弧焊接头组织和冲击性能分析

在焊接过程中X80管线钢焊接热影响区和焊缝组织性能产生显著变化,特别是焊接热影响区粗晶区的低温冲击性能变化明显,因此针对X80管线钢制订相应的螺旋埋弧焊工艺,对其螺旋埋弧焊管焊缝和热影响区粗晶区(CGHAZ)和细晶区(FGHAZ)的组织和冲击性能进行分析。结果表明,与母材相比,CGHAZ的晶粒尺寸较大,低温冲击韧性较低,韧脆转变温度在-20℃和-40℃之间;FGHAZ晶粒细小而均匀,是焊接接头冲击性能较好的区域,在-60℃时冲击韧性值达到144 J;同时通过扫描电镜分析了CGHAZ和FGHAZ常温冲击断口形貌,CGHAZ塑性断口区是小而浅的韧窝,而FGHAZ塑性断口区为大而深的韧窝。     

不同成分X80管线钢焊接接头组织性能研究

利用多丝埋弧焊设备模拟制管过程的焊接工艺进行了不同成分X80管线钢双丝埋弧焊焊接试验,通过拉伸、冲击试验检测了接头的力学性能,通过光学显微镜、扫描电镜(SEM)、透射电镜(TEM)以及电子背散射衍射(EBSD)分析了不同成分X80管线钢焊接接头的显微组织、马/奥组元(M/A)分布及形态。结果表明:随着合金含量降低,经济型X80管线钢接头的冲击韧性离散度增大。热影响区晶粒尺寸离散度增加,晶粒取向单一,大角度晶界(15°)密度显著降低是经济型X80管线钢焊接热影响区冲击韧性离散性增加主要原因。     

焊接接头的强度

X80级管线钢冲击韧性及其有效晶粒研究,多丝埋弧焊热影响区冲击韧性分析,芜湖长江大桥钢梁焊接接头性能研究,ADB610D钢焊接接头冲击吸收功的统计分布模型,DP590GA热镀锌双相钢电阻点焊接头性能。     

焊接接头的强度

X80级管线钢冲击韧性及其有效晶粒研究,多丝埋弧焊热影响区冲击韧性分析,芜湖长江大桥钢梁焊接接头性能研究,ADB610D钢焊接接头冲击吸收功的统计分布模型,DP590GA热镀锌双相钢电阻点焊接头性能。     

X80螺旋埋弧焊管的性能分析

在X80管线钢卷板的性能符合西气东输要求的情况下,研究了其螺旋埋弧焊管的组织形貌、力学性能和维氏硬度.研究表明:X80管线钢螺旋焊管焊接接头形貌良好,焊缝、热影响区的晶粒细小,组织合理:力学性能优良,-10℃管体、焊缝和热影响区的冲击功分别为267、147和96J,剪切面积分别为98%、78%、49%,0℃管体DWTT剪切面积为100%;硬度均低于275HV10,各项指标均满足西气东输X80管线钢螺旋焊管要求.     

X80钢低温焊接接头组织与性能研究

为了研究X80管线钢在低温环境下焊接的接头性能,本文对X80钢采用焊条电弧焊模拟不同温度条件进行焊接,并对获得的焊接接头进行拉伸试验、冲击试验、硬度测试及金相观察,利用SEM观察焊接接头断口形貌。结果表明:X80钢在低温环境下焊接接头的拉伸强度、冲击韧性等力学性能都较常温环境下低,而硬度值有所上升;随着焊接温度的降低,X80钢焊接接头的断裂方式由韧性断裂逐渐转变为脆性断裂。     

Reel铺设弯曲过程对X65海管焊接接头力学性能的影响

利用自主设计的弯管试验机对准101.6 mm×14.3 mm的X65级焊接管线钢进行了Reel铺设弯曲模拟试验,并通过拉伸试验、弯曲试验和冲击试验评价了Reel铺设弯曲过程对X65海管焊接接头环焊缝的拉伸性能、弯曲性能和低温冲击韧性的影响。试验结果表明,弯曲前后的X65级管线钢的GTAW焊接接头的各项力学性能均能满足相关标准要求。     

X100钢级螺旋缝埋弧焊管制造技术研究

介绍了X100钢级管线钢板卷螺旋缝埋弧焊接制管的过程;研究了X100钢级板卷的力学性能及不同焊接材料匹配对焊接接头强度、韧性和硬度的影响;提出了不去除螺旋缝埋弧焊管焊缝余高,优化板卷合金成分、提高板卷层流冷却速度及降低焊接热输入量,管体横向拉伸试验采用圆棒试样,制定X100钢级管线钢板卷和螺旋缝埋弧焊管标准等建议。     

超低碳贝氏体高强度钢焊接接头强韧性表征

采用焊条电弧焊、埋弧自动焊和焊接热模拟试验对控轧控冷工艺生产的超低碳贝氏体高强度厚钢板进行了焊接性能研究.结果表明,焊接热影响区具有较小的硬度差异.焊条电弧焊、埋弧自动焊实际焊接接头中热影响区硬度的最大差值小于60HV10,与相同级别低合金高强度钢相比,焊接热影响区强度的均匀性显著提高.焊接热影响区具有高的低温冲击韧性.当焊接热输入为56kJ/cm时,模拟过热区-40℃冲击吸收功可达到60J以上.在焊条电弧焊、埋弧自动焊实际焊接工艺条件下,焊接热影响区的-40℃冲击吸收功可达到100J以上.     

新型的治疗阿尔茨海默氏症药物(1-二甲基磷酰基-2,2,2-三氯)-乙基-1-醇烟酸醋对体外神经细胞的作用

目的: 观察本实验室合成的一种治疗阿尔茨海默氏症(AD)的药物(1-二甲基磷酰基-2, 2, 2 -三氯)-乙基^-1-醇烟酸醋(NMF),对体外培养的皮层神经细胞活性的影响以及对海人藻酸(KA)所致的神经损伤的保护作用。方法: 采用体外培养皮层神经元的方法,解剖分离 15 d胚胎小鼠皮层神经细胞, 接种于 96孔板,48 h 后加药并培养 72 h,以 MIT 法 观察 NMF 对小鼠皮层神经细胞活性的影响;同时将接种于 24 孔板的细胞预先给予 NMF,d 3 时加或不加KA处理后,以台盼蓝染色鉴别并计数死、活细胞,可得出细胞的存活率。结果: NMF 明显促进胎鼠皮层神经元活性,其中 NMF1、0. 1、10nmol·L^-1促进神经元活性增殖率分别高达 34.7%、37.4%、36. 7%, NMF 明显促进正常胎鼠皮层神经元存活卒,与对照组比较,10nmol·L^-1 NMF 对皮层神经元的存活率分别提高 39.3%、73.5%。 NMF能显著 对抗 KA 所致的神经元损伤,与 KA 损伤组相比, NMF0.1、10、10nmol·L^-1对损伤皮层神经元的保护率分别为 77.30%、80.10%、84.15%。结论: NMF 明 显促进胎鼠皮层神经元的洁性、提高正常皮层神经元,的存活卒,并能有效地保护KA所致的神经元损伤,提示 NMF 是一种很有潜力的治疗 AD 的药物。     

Three-Dimensional Growth of Coherent Ferrite in Austenite: A Molecular Dynamics Study

Coherent second phase often exhibits anisotropic morphology with specifi c orientations with respect to both the second and the matrix phases. As a key feature of microstructure, the morphology of the coherent particles is essential for understanding the second-phase strengthening eff ect in various industrial alloys. This letter reports anisotropic growth of coherent ferrite from austenite matrix in pure iron based on molecular dynamics simulation. We found that the ferrite grain tends to grow into an elongated plate-like shape, independent of its initial confi guration. The fi nal shape of the ferrite is closely related to the misfi t between the two phases, with the longest direction and the broad facet of the plate being, respectively, consistent with the best matching direction and the best matching plane calculated via the Burgers vector content(BVC) method. The strain energy calculation in the framework of Eshelby's inclusion theory verifi es that the simulated orientation of the coherent ferrite is energetically favorable. It is anticipated that the BVC method will be applicable in analysis of anisotropic growth and morphology of coherent second phase in other phase transformation systems.     

Effect of Short-Time Aging on the Pitting Corrosion Behavior of a Novel Lean Duplex Stainless Steel 2002

The effect of short-time aging in the temperature range between 400 and 1000 °C on the pitting corrosion behavior and mechanical property of a novel lean duplex stainless steel(LDSS) 2002 was investigated through the potentiostatic critical pitting temperature(CPT) tests and the Charpy impact tests. Both the pitting corrosion resistance and the toughness of aged specimens degraded due to the precipitation of detrimental secondary phases and the most significant reduction of CPT and impact energy emerged at 650 °C concurrently. The CPT of LDSS 2002 specimen aged at 650 °C decreased by 28 °C, and the impact energy dropped from 69 to 29 J/cm~2 compared with the solution-annealed sample. Transmission electron microscopy characterization showed that the main precipitates in LDSS 2002 were Cr_2N and M_(23)C_6 along the ferrite–austenite grain boundaries.     

INTRODUCTION TO PATENTS

The invention provides a method of making a mold which can reduce SOx generation rate while preventing decrease in hardening rate in the case of using sulfuric acid for a hardener composition. The method has a mixture step in which fire-resistant particles, a hardener composition and a binder composition are mixed to obtain a composition for a mold. The hardener composition contains sulfuric acid. In the mixture step, sodium carbonate is added. A molar ratio of the sulfuric acid to the sodium carbonate is 0.5 or more and 4.0 or less.     

China Foundry Week 2014

China Foundry Week, hosted by the Foundry Institution of Chinese Mechanical Engineering Society （FICMES） each year, is a large academic event in China. It is one of the ten high-impact activities sponsored by the Chinese Mechanical Engineering Society.     

17th Conference of Hydrodynamic and Electromechanical Control Engineering Call for papers

正1.Contents In order to promote the academic exchanges and technical communication of the research in the field of fluid power transmission and control,fluid control engineering specialized committee of the Chinese Society of Theoretical and Applied Mechanics will hold the 17th Conference of Hydrodynamic and Electromechanical Control Engineering on July 27-29,2014 in Tibet,Lhasa city.     

Information for Contributors

正The Transactions of Nonferrous Metals Society of China,founded in 1991 and sponsored by The Nonferrous Metals Society of China,is published monthly now and mainly contains reports of original research which reflect the new progresses in the field of nonferrous metals science and technology,including mineral processing,extraction metallurgy,metallic materials and heat treatments,metal working,physical metallurgy,powder metallurgy,with the emphasis     

Preface

<正>We are pleased to present this Special Issue of Transactions of Nonferrous Metals Society of China containing selected papers from the First Asian Conference on Aluminum Alloys(ACAA-2013),held in Beijing,China,13–17 October 2013.This conference has been initiated,with approval of     

Information for Contributors

The Transactions of Nonferrous Metals Society of China, founded in 1991 and sponsored by The Nonferrous Metals Society of China, is published monthly now and mainly contains reports of original research which reflect the new progresses in the field of nonferrous metals science and technology, including mineral processing, extraction metallurgy, metallic materials and heat treatments, metal working, physical metallurgy, powder metallurgy, with the emphasis on fundamental science. It is the unique preeminent publication in English for scientists, engineers, under/post-graduates on the field of nonferrous metals industry. This journal is covered by many famous abstract/index systems and databases such as SCI Expanded, Ei Compendex Plus, 1NSPEC, CA, METADEX, AJ and JICST.     

Rheology Feature of Simple Metal Melt

The rheology feature of Sb, Bi melt and alloys was studied using coaxial cylinder high-temperature viscometer. The results showed that the curve of torsion-rotational speed for Sb melt presents a linear relation in all measured temperature ranges, whereas for the Bi melt, the curve presents obvious non-Newtonian feature within the low temperature range and at relative high shear stress. The rheology feature of Sb80Bi20 and Sb20Bi80 alloy melts was well correlated with that of Sb and Bi, respectively. It is considered that the rheology behavior of Sb melt plays a crucial role in Sb80Bi20 alloy and that of Bi melt plays a crucial role in Sb20Bi80 alloy.