·358· 北京科技大学学报 1998年第4期 析出引起沿晶断裂. 致谢参与工作的还有徐海钢、王明璋、金梅、隋开葭等同志，在此表示感谢！ 参考文献 1 Keown S R.Physical Metallurgy of Fecralloy.In:Stainless Steels'87.New York:The Institute of Metals,1988.345 2 Giler RR.Electrical Heating,Elements.In:Bever Michael B,Editor-chief.Encyclopedia of Materials Science and Engineering(2),1986.1367 3杜国维，杜永良，章小雁.铁铬铝合金晶粒长大及合金中稀土元素，北京钢铁学院学报，1988,10(3)：368 4李培，孟广恩，吴双霞.低跪性FCrA1合金研制.金属学报，1992,28(10)：1121 5杜国维，蔡家敏，章小雁.α相形成与铁铬铝合金脆性.北京科技大学学报，1989,11(1)：63 6 Cahn R W,Hassen P.Physical Metallurgy.3rd ed.North-Holland Amstardam Prees.1983 7杜国维，蔡家敏，马如璋.热循环过程铁铬铝合金中α相沉淀.北京科技大学学报，1995,17(4)：387 8 Doing P,Liewit P E J.Nonequilibrium Solute Segregation to Austenite Grain Boundaries in Low Alloy Ferritc and Austenitc Steels.Metall Trans,1987,18A:399 9 Du Guowei,Cai Jiamin,Xiao Zhigang.TEM Studies of Cross Sections of Oxidized Fe-25Cr-6Al-La Alloy.Oxidation of Metals,1995,44(3/4):417 Fracture of Fe-Cr-Al Alloy Du Guowei Cai Jiamin Lin Shi Applied Science School,UST Beijing,Beijing 100083,China ABSTRACT The fracture of Fe-25Cr-5Al alloy has been studied.Above 1000C,grains of the alloy grow quickly.When grain size(d)increases to 80 um,the fracturs mode transited from dimple pattern to quasi-cleavage fracture;d 100 um,fracture surface appeares cleavage fracture.During thermal cycling treatment process,due to non-equilibrium segregation of chromium to grain boundaries,precpitation of micrometer scale of a -phases can occur at grain boundaries the formation of o-phase can result in intergranular fracture. K EY WORDS grain size;cleavage fracture;a -phase;o-phase