材料期刊网，材料期刊，材料类期刊，材料期刊投稿

Decomposition processes of the quenched Zn-Al alloys were studied by differentiai scanning calorimetry (DSC), X-ray diffraction (XRD) and transmission electron microscopy (TEM). The results show that the stabilities of supersaturated solid solution (SSS) of Zn-Al alloy and c' phase formed by quenching would reduce with increasing Zn content and precipitating η-Zn phases even when aging at ambient temperature,so that exothermic precipitation peak in DSC curve would disappear. The activation energy of the η-Zn precipitation and their reaction enthalpy were calculated and measured. The kinetics of α' decomposition or η-Zn formation was determined by XRD.The microstructure change during aging was observed by TEM.

关键词: differential scanning calorimetry (DSC) , null , null , null

MICROSTRUCTURE ANALYSIS OF AN ION-NITRIDING LAER ON A NO.45 STEEL

X.L. Xu , L. Wang , Z. W. Yu and Z.K. Hei(Institute of Metal and Technology , Dalian Maritime University , Dalian 116024 , China)

金属学报(英文版)

The cross-sectional microstructure of an ion-nitrided layer on a No.45 steel was studied by transmission electron microscopy (TEM). The results show that the columnar crystals constitute the compound layer. Most of them have the microstructure of alternating ε-Fe2-3N and γ-Fe4N and others are single ε-Fe2-3N phase. There are abnormal strip ferrites between the columnar crystals. The transition layer mainly consists of spherical γ-Fe4N and cementite (Fe3C) particles in the pearlite are dissolved in this layer. In diffusion layer, besides the equilibrium phase γ-Fe4N, there are α -Fe16N2 and the satellite spots around main spots of α-Fe16N2 demonstrate its modulation structure. A metastable ordered cluster zone of the nitropen atoms was found in the division layer.

关键词: ion nitriding , null , null

承钢公司成功试炼X70、C700L两钢种

钢铁

近日，承钢公司试炼管线钢X70、卷板C700L获成功，钢坯成分、气体含量、铸坯质量等指标均达到标准要求。管线钢X70是具有高强度、高韧性和良好焊接性能的高级别管线。提钒钢轧二厂在总结以往管线钢生产经验的基础上，于4月15日对X70钢组织试制，

关键词: X70 , 钢种 , 试炼 , 管线钢 , 气体含量 , 铸坯质量 , 焊接性能 , 生产经验

X80管线钢在0.5 mol/L NaHCO3+0.02 mol/L NaCl溶液中的点腐蚀性能

梁平 , 李晓刚 , 杜翠薇 , 陈旭

腐蚀与防护

采用动电位极化和电化学阻抗法研究了X80和X70管线钢在0.5 mol/L NaHCO3+0.02 mol/L NaCl溶液中的腐蚀行为,并通过电容测量方法对其腐蚀机理进行了探讨.结果表明:在0.5 mol/L NaHCO3+0.02 mol/L NaCl溶液中,X80管线钢的点腐蚀电位Epit比X70钢的要正一些,发生点腐蚀的倾向性更小.Mott-Sehottky分析表明:X80比X70管线钢表面钝化膜内的施主密度更低,缺陷数量更少,从而减少了点腐蚀萌生的潜在位置,使X80钢比X70钢具有更好的耐点蚀性能.

关键词: X80管线钢 , 点蚀 , 莫特一肖特基分析

316L/X65复合管弧焊工艺研究

黄本生 , 陈鹏 , 张荣副 , 龚成龙 , 苑评 , 代丽 , 胡梦笛

材料导报 doi:10.11896/j.issn.1005-023X.2016.06.024

采用手工钨极氩弧焊和电弧焊实现了316L/X65双合金复合管的对接焊接.为了研究复合管的焊接工艺,对焊接接头进行了硬度、拉伸和冲击测试,利用光学显微镜、扫描电镜和能谱仪分析了接头的微观结构和成分特点,并对接头进行了电化学实验.结果表明:复合管焊缝由碳钢层、扩散层、过渡层和不锈钢层组成,碳钢层主要为针状铁素体,扩散层出现了马氏体组织,过渡层和不锈钢层焊缝中铁素体呈骨架或蠕虫状分布在奥氏体晶界;本实验焊接工艺下,覆层未受到碳钢层的稀释,化学成分与母材基本一致,但耐蚀性略有降低;焊接接头各项力学性能良好.

关键词: 316L/X65 , 复合管 , 焊接工艺 , 显微组织 , 性能

复合管X65/316L在模拟产出水中的电偶腐蚀行为

邓洪达 , 曾顺鹏

腐蚀与防护 doi:10.11973/fsyfh-201508007

海洋天然气输送用复合金属管内外层因内层金属输送介质渗漏将构建电偶对,加速外层金属腐蚀.本工作采用浸泡试验和电化学技术分析X65-316L电偶对在模拟产出水中的电偶腐蚀行为.采用SEM观察电偶对金属腐蚀前后形貌变化;分析X65和316L偶接前后开路电位(OCP)和偶接电流密度(Jcc)随时间的变化曲线,以及其对电化学参数的影响.结果显示,X65-316L电偶对在模拟产出水中X65为阳极,316L为阴极;与偶接前相比,X65腐蚀速率增加,316L腐蚀速率下降,同时X65阴极极化率减小,316L阳极极化率增加.

关键词: 复合管 , 电偶腐蚀 , SEM , 电化学技术

INVESTIGATION OF BONDING IN NANO-SiO2 BY Si L2,3 X-RAY ABSORPTION NEAR-EDGE STRUCTURE SPECTROSCOPY

Z.Y. Wu

金属学报(英文版)

The Si L2,3 X-ray absorption near-edge structure (XANES) can be used to probe thelocal structure around Si and derive electronic information of the unoccupied s- andd-like partial density of states in nano-size SiO2. We present Si L2,3-edge for threedifferent size silicates acquired by total electron yield (TEY) at the photoemission sta-tion of Beijing Synchrotron Radiation Facility (BSRF). The Si L2,3-edge spectra areinterpreted based on ab initio full multiple-scattering (MS) calculation. The Si L2.3-edge of nano-size materials has XANES similar to that of a-quartz. The similaritiesbetween the Si L2.3-edge shapes attest to a common molecular-orbital picture of theirSi-O bonding and the same coordination state. However, a considerable broadeningof Si L2,3-edge XANES spectra as decrease of particle size is also an indicative ofpolyhedral distortions.

关键词: multiple scattering calculation , null , null , null

API X65、316L不锈钢及Inconel 625间电偶腐蚀风险研究

田永芹 , 常炜 , 胡丽华 , 贾旭 , 周晓红 , 邢云颖 , 余晓毅 , 于湉

表面技术 doi:10.16490/j.cnki.issn.1001-3660.2016.05.020

目的：确定API X65、316L不锈钢及inconel625相互偶接后的电偶腐蚀风险。方法采用电化学测试、标准电偶腐蚀评价实验和腐蚀模拟实验对电偶腐蚀进行分析研究。结果在模拟地层水中，经过电化学测试，X65的自腐蚀电位在-0.75 V左右，316L和625的电位在-0.35 V左右。对于标准电偶腐蚀评价实验，敞口溶液及CO2分压分别为100 kPa和500 kPa的溶液中，X65与316L之间的电偶电流最大，其次是X65与625，316L和625之间的电偶电流最小，几乎为零。通过电偶腐蚀模拟试验可知，X65与316L或625偶接，都发生了明显的电偶腐蚀，而且X65侧靠近焊接接头位置发生了严重的沟槽腐蚀，未偶接异金属时X65的平均腐蚀速率为1.24 mm/a，异金属接触导致的电偶腐蚀使X65的腐蚀速率增加， X65与316L偶接后的平均腐蚀速率为1.49 mm/a，X65与625偶接后的平均腐蚀速率为1.75 mm/a。X65与316L偶接后的局部腐蚀速率最大为16.8 mm/a，X65与625偶接后的局部腐蚀速率高达26.4 mm/a，由于电偶腐蚀导致的局部腐蚀速率要比X65的自腐蚀速率超出十几倍。X65与316L偶接的电偶腐蚀的速率要比X65和625偶接的大，316L和625间几乎没有电偶腐蚀发生。结论 X65、316L和625间偶接的电偶腐蚀风险大于X65与316L的，316L和625间偶接的电偶腐蚀风险较小。

关键词: 316L , API X65 , inconel625 , 电偶腐蚀 , 电化学测试 , 模拟试验

X80钢在0.5mol/L NaCl溶液中的交流电流腐蚀行为

王霞 , 张鹏 , 王飞 , 吴红梅

腐蚀与防护 doi:10.11973/fsyfh-201508008

采用极化曲线、电化学阻抗谱(EIS)、金相显微镜等方法,研究了不同交流电流密度作用下X80钢在0.5 mol/L NaCl溶液中的腐蚀行为.结果表明,随着交流电流密度的升高,X80在NaCl溶液中的腐蚀电位均较负,腐蚀电流密度出现波动,阳、阴极Tafel斜率的比值出现大幅度变化,极化电阻和低频区阻抗模值也均出现波动;X80钢表面出现越来越多的大点蚀坑及分布较均匀的小点蚀坑,局部腐蚀严重.

关键词: X80 , 交流电流密度 , 氯离子 , 腐蚀