The 1100 ℃ isothermal oxidation behavior of Fe-23Cr-5Al alloy modified by yttrium addition was studied by means of thermogravimetric analysis, scanning electron microscopy and energy dispersive X-ray analysis. Yttrium was added to this alloy in the forms of metallic addition, yttrium oxide and ion implant. Cracking and spalling occurred on the convoluted scale formed on Y-free alloy and exposed the substrate. A flat dense scale without spallation was formed on the yttrium alloying addition or yttrium oxide dispersion alloy. The scale adhesion was also improved by 1×1017Y＋／cm2-implantation. The results indicate the convoluted morphology of the scale on Fe-23Cr-5Al-0.21Ti alloy is related to the growth mechanism of the alumina scale, and the spallation of the scale is related to sulfur segregation at the scale/alloy interface. The main reason that the adhesion of alumina scale is improved by yttrium addition lies in the following. Yttrium is liable to form a stable yttrium sulfide with sulfur in the alloy and prevent sulfur interface from segregation. Another reason is that the growth mechanism of alumina scale is changed by yttrium addition.
参考文献
| [1] | Moon D P .Role of reactive elements in alloy protection[J].Materials Science and Technology,1989,5(08):754-764. |
| [2] | Evans H E .Cracking and spalling of protective oxide layers[J].Materials Science and Engineering,1989,A120:139-146. |
| [3] | Golightly F A;STOTT F H;WOOD G C .The influence of yttrium additions on the oxide-scale adhesion to an iron-chromium-aluminum alloy[J].Oxidation of Metals,1976,10(03):163-187. |
| [4] | Tolpygo V K;GRABKE H J .Microstructure characterization and adherence of α-Al2O3 oxide[J].Oxidation of Metals,1994,41(5-6):343-363. |
| [5] | Norin A .Mechanical stresses developed in austenitic Fe-Cr-Ni alloys by oxidation in CO2 atmosphere[J].Oxidation of Metals,1975,9(03):259-273. |
| [6] | Hou P Y;STRINGER J .Oxide scale adhesion and impurity segregation at the scale/metal interface[J].Oxidation of Metals,1992,38(5-6):323-363. |
| [7] | SIGLER D R .Aluminum oxide adherence on Fe-Cr-Al alloys modified with group ⅢB,ⅣB,ⅤB,and ⅥB elements[J].Oxidation of Metals,1989,32(5-6):337-355. |
| [8] | SIGLER D R .Adherence behavior of oxide grown in air and synthetic exhaust gas on Fe-Cr-Al alloys containing strong sulfide-forming elements: Ca,Mg,Y,Ce,La,Ti,and Zr[J].Oxidation of Metals,1993,40(5-6):555-583. |
| [9] | Jedlinski J;BORCHARDT G .On the oxidation mechanism of alumina formers[J].Oxidation of Metals,1991,36(3-4):317-337. |
| [10] | 辛丽,李美栓,钱余海,李铁藩.Influences of Yttrium on Cyclic Oxidation Behavior of Fe-Cr-Al Alloy[J].中国稀土学报(英文版),2001(01):53-56. |
- 下载量()
- 访问量()
- 您的评分：
-
10%
-
20%
-
30%
-
40%
-
50%