【摘要】 本文利用金相、电子探针、扫描电镜、Ｘ射线衍射等手段对制氢转化炉ＨＫ４０ 翻边法兰的周向穿透裂纹进行了研究．结果表明．翻边法兰周向穿透裂纹的产生是由应 力氧化引起的。翻边法兰在装配时受到弯曲应力。裂纹内壁氧化腐蚀的产物是由两层 组成的，内层为富铬的氧化物（Ｆｅ，Ｎｉ）Ｃｒ２Ｏ４，外层为富铁的氧化物Ｆｅ２Ｏ３更多还原

【Abstract】 The circumferentially penetrating cracks on the flange of HK 40 in petro- chemical reformer furnace have been in vestigated by means of metallography, electronic probe, scanning microscope and X-ray diffraction. It is shown that the circumferentially penetrating cracks on the flange are produced by stress oxidation. The flange bears bending stress when assembled. The oxidation products are composed of two layers. The oxide (Fe, Ni) Cr2O4 with rich Cr is inside layer and the oxide Fe2O3 with rich Fe is outside layer.更多还原