(1. 北京科技大学 材料科学与工程学院，北京 100083；
2. 北京科技大学 新金属材料国家重点实验室，北京 100083)
摘 要:
关键字: 高纯铝；晶面指数；位错；腐蚀发孔；表面
（1. School of Materials Science and Engineering, University of Science and Technology Beijing, Beijing 100083, China;
2. State Key Laboratory of Advanced Metals and Materials, University of Science and Technology Beijing,Beijing 100083, China）
Abstract:The solution containing hydrochloric acid, nitric acid and hydrofluoric acid was used to etch the {100} and {124} surfaces of single crystal which were cut from ingot of high purity aluminum. The densities evolvement of pitting holes on the surfaces of the samples was quantitatively and statistically analyzed during the etching process, of which the regularity was obtained by the nonlinear fitting regression. It was observed that the pit etching initiates at the locations of dislocation ends on the samples surface. The difficulty of the pit etching was related to the strain energy of corresponding dislocations. The results show that density of potential pit nucleation on {100} surface is higher than that on {124} surface, and the primary nucleation rate of pit etching on {100} surface is lower than that on {124} surface. Pitting holes on {124} surface grow faster than those on {100} surface because the surface energy on {124} surface is higher than that on {100}, which leads to obviously lower pitting hole density on {124} after long etching treatment.
Key words: high purity aluminum; miller indices; dislocation; pit etching, surface
