王旭
,
张俊善
,
雷明凯
金属学报
利用离子能量为300 keV、束流密度为200 A/cm2、脉冲宽度为75 ns的混合离子束(70%H++30%C+)组成的强流脉冲离子束(HIPIB)对316L不锈钢进行了表面辐照处理, 辐照次数分别为1, 5, 10次. 采用SEM, XRD, TEM和EPMA分析辐照后试样表面形貌、表面层相组成和微观结构及元素分布的变化. 结果表明, HIPIB辐照使试样表面光滑化, 表面层晶粒细化、产生择优取向, 杂质元素选择性烧蚀, 电化学腐蚀性能明显提高. 由于HIPIB辐照引起的大应力和冲击波的影响, 辐照后在深度达100μm表层内显微硬度提高, 表面摩擦系数降低, 表面抗磨损性能显著改善.随着辐照次数的增加, 316L疲劳极限和蠕变断裂寿命延长, 稳态蠕变速率降低.
关键词:
强流脉冲离子束
,
316L stainless steel
,
surface modification
王松涛
,
杨柯
,
单以银
,
李来风
金属学报
冷变形是提高奥氏体不锈钢强度的有效手段。本文以一种含氮量达1.0wt.%的高氮奥氏体不锈钢和316L不锈钢为研究对象，通过在室温下对这两种材料施加不同的压缩变形量，研究了两种材料变形后的显微组织、真应力-应变曲线、显微硬度。结果表明，两种材料在冷变形量小于20%时，机械孪晶和滑移共同参与变形。随变形量增加至50%，316L的变形方式过渡到以滑移为主，而高氮钢中机械孪晶和滑移仍共同参与变形。高氮奥氏体不锈钢在变形过程中不发生马氏体相变，表明其具有较高的结构稳定性，而316L中有马氏体形成。高氮不锈钢的固溶态强度、硬度和加工硬化系数均显著高于316L，冷变形可大幅提高两种材料的强度。两种材料的显微硬度均与晶粒取向有明显相关性，晶粒取向对显微硬度的影响大于变形的不均匀性。本文还对高氮不锈钢表现出的优异性能的机制进行了分析和讨论。
关键词:
高氮奥氏体不锈钢
,
316L stainless steel
,
cold deformation
Ali Parsapour
材料科学技术（英文）
Surface engineering technology is a suitable method for coatings on the metal surfaces or performing surface modification treatment, which can improve corrosion resistance and biocompatibility of metals. In this research, corrosion behavior of Nb coating on H2SO4 and HNO3 treated AISI stainless steel 316L (SS) was evaluated. Nb coating was carried out using physical vapor deposition process on the SS. Characterization techniques including scanning electron microscopy (SEM) and energy dispersive X-ray (EDX) technique were used to investigate the microstructure and morphology of the coated and treated SS. Electrochemical potentiodynamic tests were performed in two types of physiological solutions and compared with the pristine SS specimens.
Cyclic polarization tests were performed to evaluate resistivity against pitting. Experimental results indicate that Nb coating and surface treatment of the SS had a positive effect on improvement of corrosion behavior. The decrease in corrosion current densities was significant for coated and treated specimens. The corrosion current density was much lower than the values obtained for pristine specimens.
关键词:
316L stainless steel
A.Q. Lü
,
Y. Zhang
金属学报(英文版)
By means of surface mechanical attrition treatment (SMAT), the grain size with a diameter of about 60nm formed at about 20μm depth and numerous mechanical twins at about 50μm depth from the treated surface were synthesized in 316L stainless steel because of the different distributions of strain and strain rate along depth orientation. For instance the maximum strain rate reached 103-104s-1 on the top surface. The relationship between the microstructure and the corrosion property was studied in 0.05M H2SO4+ 0.25M Na2SO4 aqueous solution, and the results show an extreme improvement of corrosion resistance owing to the appearance of twin boundaries and the obvious reduction in corrosion resistance attributed to the presence of nanocrystaline boundaries.
KEY WORDS surface mechanical attrition trea
关键词:
surface mechanical attrition treatment
,
腐蚀性能
,
孪晶界
,
纳米晶界
杨远航
,
李晓琳
,
刘文斌
,
顾艳红
,
车俊铁
材料保护
为了探究316L不锈钢焊缝腐蚀微电池的形成机理,通过微观组织观察及电化学试验进行了分析.采用扫描电镜(SEM)对焊件三区(焊缝区、热影响区、母材区)的形貌及元素组成进行了观察分析,采用金相显微镜观察微观组织,并确定晶粒度及非金属夹杂物及其分布.结果表明:316L不锈钢焊缝形成腐蚀微电池的倾向与元素组成、非金属夹杂物和晶粒度大小等因素紧密相关;焊缝三区腐蚀电位、腐蚀电流不同,耐蚀性能差异较大,因而腐蚀电位最低的热影响区与腐蚀电位最高的母材区在电解液中比较容易形成腐蚀微电池,且热影响区可视为此微电池的阳极,腐蚀进程较快.
关键词:
腐蚀微电池
,
形成机理
,
316L不锈钢
,
焊缝
,
微观组织
,
极化曲线
,
电化学阻抗谱
卢向雨
,
姚胜
,
唐俊荣
,
赵刘明
,
冯兴国
表面技术
doi:10.16490/j.cnki.issn.1001-3660.2015.12.002
目的 研究316L不锈钢TIG焊接接头各区域在不同浓度H2S溶液中的钝化及耐蚀性能差异.方法 在H2S质量浓度为0. 05,0. 1,0. 2,0. 4,0. 8 g/L的H2S溶液中,通过极化曲线、恒电位阶跃、阳极极化、交流阻抗等方法,分别研究316 L奥氏体不锈钢TIG焊接接头的母材区和焊缝区的钝化性及耐蚀性能.结果 随着H2S浓度的增加,焊接接头母材区和焊缝区的钝化性能都所有降低,电化学活性都明显升高,且腐蚀电位逐渐降低,腐蚀电流密度有所增加. 交流阻抗拟合结果显示,母材区和焊缝区的抗腐蚀性能指标( R1+R2 )随着H2S浓度的升高而降低. 此外,在相同浓度的H2S溶液中,焊缝区的腐蚀电位、钝化性能、阻抗都比母材区低,而电化学活性、腐蚀电流密度都比母材区高. 同时,随着H2S浓度的升高,焊缝区与母材区的钝化性能、耐腐蚀性差距逐渐变大. 结论 随着H2S溶液浓度的增加,316L不锈钢TIG焊接接头母材区和焊缝区的钝化性能逐渐降低,耐蚀性下降,且二者耐蚀性的差距逐渐加大. 在相同浓度的H2S溶液中,母材区的耐蚀性比焊缝区好.
关键词:
316L不锈钢
,
钨极惰性气体保护焊
,
硫化氢溶液
,
腐蚀
,
钝化
