Mechanical properties and oxidation formation of EB-PVD deposited Ni-Cr-Al alloy
来源期刊:中国有色金属学报(英文版)2005年第z3期
论文作者:关春龙 栗政新 赫晓东
文章页码:64 - 65
Key words:EB-PVD; mechanical properties; oxide formation; Ni-Cr-Al alloy
Abstract: Ni-20Cr-0.6Al(molar fraction, %) alloy sheet with 0.2mm in thickness was deposited at 900℃ from a target of Ni-Cr-Al alloy by EB-PVD. The grain size of as-deposited alloy was less than 100nm. The mechanical properties of alloys were examined using room tensile tests. The ultimate tensile strength of as-deposited and annealed films was 780MPa and 767MPa, respectively. Investigation of fracture surfaces from samples reveals that brittle fracture takes place along boundaries of columnar crystals formed on the substrate side, while the equiaxed dimples are dominant on the evaporation side. Oxide formation of Ni-20Cr-0.6Al alloy after 100h oxidation at 1000℃ in air was studied. The results indicate that a continuous and dense α-Al2O3 scale is formed after 100h oxidation for as-deposited alloy, while a complex oxide scale, consisting of the outer oxide layer of Cr2O3, NiO and NiCr2O4 and the inner oxide layer of Al2O3, forms for annealed alloy.