材料期刊网

<正> 电沉积Ni-P合金时,只要沉积层中的磷含量大于8at％就能得到非晶态。 尽管化学镀Ni-P已作为防护工程的一种标准镀层,而电镀Ni-P台金的研究还相当有限。本工作就电镀非晶态Ni-P合金在若干酸中的腐蚀行为进行了研究。

Ni-P amorphous alloy (a.a.)with four different phosphorous contents (8, 10, 12, 14 wr%P)were electro-deposited.The corrosion rates of these electrodeposits in H_2SO_4, HCl, HNO_2, NaOH and FeCl_3·6H_2O solutions were measured and the corrosion products were examined by means of SEM, X-ray diffraction and XPS.The electrochemical parameters of thc electrodeposits in 1M H_2SO_4, 1M HCl and 1M HNO_3 were also determined.The test results showed that: 1) The corrosion resistance of the electrodeposited Ni-P (a.a.) was better than that of Ni. The corrosion rates of Ni-P (a.a.) decreased with the increase of P content. 2) X-ray diffraction and XPS revealed that after being immersed in H_2SO_4, HCl, and FeCl_3·6H_2O solutions, a compound-Ni_2P or Ni Py would form on the'surface of Ni-P (a.a.). 3) Free corrosion potential and anodic polarization curves of these amorphous alloys in 1M H_2SO_4, HNO_3 or HCl solutions shifted remarkably to more noble potential with increase of P content,