F.Lu
,
W.Y.Shen
,
J.G. Li and W.D. Zhen(Beijing Institute of Aeronautical Materials
,
Beijing 100095
,
China Manuscript received 26 August 1996)
金属学报(英文版)
The electrochemical approach was used to show the nature of the galvanic corrosion when graphite epoxy composite materials(GECM)were coupled to LY12CZ aluminum alloy. An open circuit potential difference of one volt was obtained in 3.5% NaCl solution between GECM and LY12CZ. Corrosion current data (zero impedance technique) indicated that there was serious corrosion at GECM/LY12CZ couple.When GECM/LY12CZ couples were exposed to ASTM salt spray and alternate immersion condition, fiber glass cloth and H06-2 epoxy primer paint were effective methods for preventing galvanic corrosion.The slow strain rate test (SSRT) showed that GECM increased the LY12CZ stress corrosion crack growth rate.
关键词:
:galvanic corrosion
,
null
MA Zongyi YAO Zhongkai Harbin Institute of Technology
,
Harbin
,
China
金属学报(英文版)
The SiC_w/Al composite prepared by squeeze casting has a combination of superior room temperature specific strength and modulus together with excellent thermal properties.The extrusion can make an improvement on the strength and ductility of the composite from 582 MPa as squeeze casted up to 639 MPa,and on the transformation from isotropic to the anisotropic structure.This seems to be explained by the orientation of whiskers and the densification of dislocations in matrix.TEM observation indicates that the stacking fault is the usual planar defect on the SiC_w surface. composite;;SiC whisker;;Al alloy;;microstructure
关键词:
composite
,
null
,
null
,
null
Doris Smith
,
Ken Lynam
环境化学
本文中使用安捷伦SPEC C18AR固相萃取膜盘成功萃取了水中的有机氯农药残留和除草剂.使用双柱配置的GC/μECD系统进行检测,安捷伦J&W DB-35ms UI超高惰性色谱柱作为分析柱,DB-XLB色谱柱为确认柱.该方法为浓度接近或低于最大污染限值的含氯有机物提供了高度灵敏的分析方法.根据预估的分析物萃取浓度,方法使用的校准范围为1-100 ng· mL-1.分别对0.01 μg·L-1的加标水样和一个自来水水样进行了萃取和分析,结果证明可满足水中的有机氯农药残留和除草剂的测定.
关键词:
有机氯农药
,
除草剂
,
色谱柱
鲁二敬
,
卢峰华
,
许鸿吉
,
谢明
,
钮旭晶
机械工程材料
通过周期浸润腐蚀试验,对比研究了S355.12W耐候钢和Q345R低合金钢在NariSOs溶液中的耐腐蚀性能,并用扫描电镜对腐蚀产物进行了观察和分析。结果表明:在相同试验条件下,S355J2W耐候钢的腐蚀速率低于Q345R钢的;S355J2W耐候钢会在表面形成黑褐色锈层,而Q345R钢表面形成橘红色易剥落的疏松锈层;S355J2W耐候钢腐蚀产物微观形貌为沿放射性方向生长的针状晶体,Q345R钢为颗粒状聚合物堆积而成,形状无规则,颗粒之间有较大的空隙。
关键词:
S355J2W耐候钢
,
周期浸润腐蚀试验
,
耐腐蚀性能
李志宏
,
柳卫平
,
白希祥
,
郭冰
,
连钢
,
颜胜权
,
王宝祥
,
陆昀
,
曾晟
,
苏俊
原子核物理评论
doi:10.3969/j.issn.1007-4627.2005.01.006
利用8Li次级束测量了质心系能量7.8 MeV 2H(8Li, 9Li)1H反应的角分布, 导出了8Li(d, p)9Li反应的天体物理S因子及9Li→8Li+n虚衰变的渐近归一化系数.
关键词:
8Li(d,p)9Li反应
,
角分布
,
天体物理S因子
,
渐近归一化系数
Journal of Applied Physics
The alloying effect of 3d transition metal elements on the lattice constants and their site preferences in gamma'-Co(3)(Al, W) are systematically studied based on a supercell model. The lattice constant of the gamma' phase is modified by the addition of 3d transition metal elements, and it increases in the order of Fe < Ni < Mn < Cr < V < Ti. Four types of site preference are identified for these 3d elements in gamma' phase by analyzing the binding energy and the impurity formation energy. Ni, Fe, V, and Ti are recognized to stabilize the gamma' phase. Their distinct alloying effect is further revealed by investigating the impurity-induced charge density difference and the partial density of states. These results are in agreement with the experimental data ever reported. (C) 2010 American Institute of Physics. [doi: 10.1063/1.3319650]
关键词:
augmented-wave method;co-base superalloy;electronic-structure;site;preference;ni3al;phase;temperature;stability;magnetism;alloys
谷晓鹏
,
段珍珍
,
邓钢
,
谷晓燕
材料工程
doi:10.11868/j.issn.1001-4381.2015.02.004
利用激光-MAG复合焊和MAG焊进行了厚板S355J2W+N低碳钢的焊接实验,分析了两种焊接方法接头的微观组织和力学性能.结果表明:复合焊和MAG焊焊缝接头均由焊缝区、过热区、重结晶区和不完全重结晶区构成,复合焊接头截面呈“高脚杯”状特点,焊缝填充量和热影响区宽度较MAG焊明显减小.复合焊由于冷却速率快,过热区魏氏组织略有增多,硬度高于MAG焊,抗拉强度和弯曲性能与MAG焊相比,无显著差异,均能够满足生产标准的要求.
关键词:
S355J2W+N
,
激光
,
MAG
,
复合焊
,
接头组织
,
性能