齐芸馨
,
唐文泰
,
夏建国
,
李望
,
展振宗
金属学报
本文采用SAM和XPS对实用Au-Ni-Kovar合金系统热处理样品(250—350℃,0.5—1.5h)进行了基底元素穿透Au层的表面偏聚研究,给出了这一复杂系统中Ni,Co表面偏聚机理的直观证据,即Ni,Co主要是通过晶界扩散穿透Au层而后以表面扩散覆盖镀Au表面的;表面偏聚元素化学态的研究则不仅表明,氧的吸附和氧化反应是Ni,Co表面偏聚的驱动力,而且发现,上述偏聚会引起样品表面吸水的现象。
关键词:
Au-Ni-Kovar合金系统
,
surface segregation
,
substrate element
,
SAM
,
XPS
QI Yunxin TANG Wentai XIA Jianguo Nei Mongol Institute of Metallic Materials
,
Baotou
,
ChinaLI Wang ZHAN Zhenzong Institute of Physical and Chemical Engineering Research
,
Tianjin
,
China
金属学报(英文版)
The surface segregation of substrate elements through the Au layer in the Au-Ni-Kovar sys- tem specimens heated at 250—350℃ for 0.5—1.5 h has been studied by SAM and XPS. Visual evidence of the mechanism for Ni and Co surface segregation of the complicated sys- tem has been given,i.e.Ni and Co penetrated the gold layer mainly by grain boundary diffu- sion and then covered the Au layer by surface diffusion.The strdy results of the chemical states of surface segregation elements not only indicate that oxygen adsorption and oxidation reaction are the driving force for the surface segregation of Ni and Co,but also show that the above segregation can result in water absorption on surfaces.
关键词:
Au-Ni-Kovar alloy system
,
null
,
null
,
null
,
null
Honggang JIANG+
,
Bingzhe DING
,
Jingtang WANG
,
State Key Lab. for RSA
,
Institute of Metal Research
,
Academia Sinica
,
Shenyang 110015
,
China
材料科学技术（英）
In Ni_(68)P_(18)Cr_(14) amorphous alloy, the dominant component elements Ni and P were in lower content in the surface layer, while Cr was enriched. There was a P enrichment region just below the surface oxide layer, which was supposed to enhance the surface segregation of Cr. Nickel was less oxidized than Cr.
关键词:
Ni_(68)P_(18)Cr_(14)amorphous alloy
,
null
黄希
,
项利
,
仇圣桃
,
宋志国
材料热处理学报
运用EBSD和光学显微镜,研究了0.25％～0.45％ Cu对无取向电工钢热轧板显微组织,成品板显微组织、织构和磁性能的影响.实验结果表明:卷取过程中Cu元素在热轧板表层的偏聚作用显著阻碍了热轧板表层再结晶晶粒长大,导致热轧板表层晶粒尺寸随着Cu含量增加而逐渐较小,但热轧板中间晶粒尺寸变化不大.同时发现Cu元素能够明显改善织构类型,使有利织构组分增加,不利织构组分减少,同时减弱织构强度.从实验结果可知0.35％ Cu能够显著改善电工钢的磁性能,铁损P15/50最低达到4.1 W/kg,磁感B50最高值达到1.8T.
关键词:
无取向电工钢
,
磁性能
,
Cu
,
表面偏聚
,
织构
辛超
,
龚洪勇
,
尹传强
,
周浪
材料科学与工程学报
实验研究了经酸洗除杂的冶金级硅粉在空气中进行高温处理以再次造成表面杂质偏聚,然后继以二次酸洗去吸附除杂的方法。结果表明这种方法因其硅粉表面形成的硅氧化物进一步提高了金属杂质表面扩散偏聚的能力,比保护气氛条件下的高温处理有更好的偏聚效果,二次酸洗后金属杂质含量进一步降低。
关键词:
冶金级硅
,
表面偏聚
,
高温处理
,
酸洗
姜洪刚
,
丁炳哲
,
王景唐
材料研究学报
用AES 原位加热的方法研究了Ni_(84)P_(16)非晶合金中磷原子的表面偏析现象。在实验温度范围内,磷向自由表面的偏析是由体扩散控制的,表面浓度C_S 随退火时间t 的变化符合Hoffmann—Erlewein关系(H—E关系)。在250—350℃温区内,磷原子单独向表面偏析,扩散系数D 位于1.1×10~(-24)—9.0×10~(-22)m~2s~(-1)之间,D 与T 符合Arrhenius 关系,其中指数前因子D_0=2.81×10~(-6)m~2s~_(-1),扩散激活能E_0=1.70eV。在380℃退火时,晶化产生的晶界加速P 偏析,同时促进Ni 向自由表面扩散。
关键词:
表面偏析
,
atomic diffusion
,
AES
