·404· 北京科技大学学报 2002年第4期 的表面都有一层氧化铁皮层，裂纹内夹着的小 颗粒有氧化铁及保护渣颗粒.氧、氨分析结果表 明：钢板边缘部分的氧质量分数为0.02%，远离 边缘区仅为46×10-%，而边缘处的氮质量分数 与钢板中部差不多，均在70×10-%~76×10‘% 之间. 2.3典型裂纹的SEM观察与X射线能谱分析 用扫描电镜对裂纹进行了仔细的观察，裂 纹处氧化铁皮与基体间界面及附近的能谱结果 图1薄板表面裂纹形貌 Fig.1 The pattern of surface crack in thin strip 如表2所示；1条典型表面裂纹的横截面及能谱 如图5，图6所示.从图表中可以看出，表面裂纹 表2裂纹及裂纹附近的能谱成分（质量分数） Table 2 Spectrum components of cracks and close-by% 编号O Al Si Cr Fe Cu Zn P Ni 1-1.052.141.0995.07 -0.771.280.7696.520.67 3 -0.762.341.7092.560.611.540.50 416.100.620.880.7281.28- 0.160.17 50.600.450.4598.49 图2薄板表面裂纹的放大像 69.520.430.930.7385.020.690.31- 2.38 Fig.2 Enlarged image of surface crack in thin strip 77.250.450.670.3690.260.480.14-0.40 86.710.670.740.5190.130.520.050.100.57 931.320.571.170.8065.280.390.170.13 1016.460.060.520.6979.621.440.350.180.67 110.030.050.450.4997.780.390.390.080.34 1221.680.071.031.0174.850.490.050.210.61 1324.770.250.490.0973.430.750.080.090.04 147.940.290.600.0689.091.660.060.070.24 154.140.230.300.0794.140.780.22 0.11 162.220.180.410.0995.860.870.07 0.29 177.970.190.460.1290.310.540.01 0.40 图3薄板边缘裂纹横断面的1幅SEM像 184.050.350.300.0694.030.71 0.49 Fig.3 The transverse section SEM picture of fringe crack 193.830.310.280.0394.100.76 0.68 in thin strip 表面 图51条典型表面裂纹的横截面 注：裂纹处氧化铁碎块与钢板基体界面处富集铜 图4薄板边缘裂纹的放大像 Fig.5 The transverse section SEM picture of a piece of Fig.4 Enlarged image of fringe crack in thin strip typical surface crack