<正> McCafferty等曾分析过Pd、Ti及Pd-Ti合金在沸腾的1MH_2SO_4介质中的阳极极化曲线,Pd向开路电位比Ti高出约1000mV;以Pd注入Ti后其电位介于Pd、Ti之间,落在Ti的钝化区域之内,能显著地提高Ti的耐蚀性。显然,Pd/Ti比愈大,耐蚀性提高得愈多。在还原性酸中,含Pd 0.2％的Ti合金耐蚀性提高1～2个数量级,但Pd-Ti体合金的内层贵金属Pd未能充分发挥作用;而以Pd~+(1-2×10~2keV,1-2×10~(16)/cm~2)注ATi,Pd的饱和原子浓度为3.5at％,耐蚀性可提高2～3个数量级。注入Pd的Ti表层中,Pd呈高斯型分布,耐蚀性随深度变化,近表面明显偏低。本工作采用离子束混合(IBM)形成Pd Ti表面合金。电子能谱剖面分析和腐蚀速率实验表明,这是一种较可取的表面改性方法。
Pd-Ti surface alloy was produced by bombarding a Pd-plated Ti alloy with Xe ions. The electron spectroscopic profile analyses show that the distribution of Pd is quite homogeneous through the surface layer, which consists of Ti, Pd and their oxides, nitrides etc. Near the surface TiO_2 is the principal component of the passive film formed. The Pd/Ti ratio is large and decreases with depth from the surface inwardly. In boiling 1NH_2SO_4 the average corrosion rate of the Pd·Ti surface alloy is about 1/60 of Ti alloy matrix after 6 hours of immersion, and corrosion rate in the near-surface region is less by three orders of magnitude. It is expected that the Pd-Ti surface alloy by IBM would be better than the Pd-Ti bulk alloy and Pd-implanted alloy for corrosion protection.
参考文献
| [1] | |
| [2] | |
| [3] | |
| [4] |
- 下载量()
- 访问量()
- 您的评分：
-
10%
-
20%
-
30%
-
40%
-
50%