分别用纳米颗粒Cr (平均尺寸62 nm), Al（平均尺寸85 nm)和微米颗粒Cr 和Al(平均尺寸3 μm)复合电沉积制备Ni-11Cr-3Al纳米复合镀层（ENC）和Ni-11Cr-7Al微米复合镀层（EMC）。纳米颗粒的复合使ENC Ni-11Cr-3Al比EMC Ni-11Cr-7Al的颗粒分布更加均匀，颗粒间距减小近25倍。900℃, 24 h恒温氧化实验表明，ENC Ni-11Cr-3Al与EMC Ni-11Cr-7Al相比氧化速率显著降低。这是由于其快速形成一层连续、致密的Cr2O3膜，进而促进其下Al2O3膜的快速形成所致。
Two electrodeposited Ni matrix composite coatings were prepared; one was Ni-11Cr-3Al (by mass%) prepared using nano-sized particles of Cr and Al and the other was Ni-11Cr-7Al composite prepared using micron-sized particles of Cr and Al. Compared with the electrodeposited micron-composite (EMC) Ni-11Cr-7Al, the electrodeposited nanocomposite (ENC) Ni-11Cr-3Al exhibited much homogeneous distribution of Cr and Al particles, because of an approximately 25-fold decrease in interparticle spacing. The significantly shorter interparticle spacing allowed the ENC Ni-11Cr-3Al to grow a continuous Cr2O3 layer first and then an Al2O3 layer underneath during a very short stage of oxidation. This is the fundamental reason for the result that the ENC, although it had a lower content of Al, was oxidized slower than the EMC Ni-11Cr-7Al during oxidation in air at 900℃. The size effect of the Cr and Al particles on the oxidation behavior of the electrodeposited Ni-Cr-Al composite coatings is discussed in detail.
参考文献
| [1] |
- 下载量()
- 访问量()
- 您的评分：
-
10%
-
20%
-
30%
-
40%
-
50%