中文摘要：

研究了车轮钢中白点形成的机理以及白点对断口形貌的影响。结果表明,氢和空位聚集导致鼓泡形核和长大,随着鼓泡内氢气压力的升高,裂纹从鼓泡核壁形核、扩展导致白点形成。白点的断口为准解理,和氢致滞后开裂断口相同,含白点试样的断口形貌依赖于断裂方式和试样厚度。钢中的白点除了产生二次裂纹和局部准解理断面外,对各种断口形貌均没有明显的影响。

英文摘要：

The mechanism of flaking in wheel steel and the effects of flaking on fracture were investigated. The resuits show that a blisters nucleate and grow through diffusion and gathering of hydrogen atoms and vacancies when the hydrogen pressure is increased, microcracks initiate at the wall of the blister,and propagate which results in formation of flaking. The fracture with flaking is quasi-cleavage, similar to that of hydrogen-induced delayed cracking. The fracture morphology of the sample containing flaking is dependent upon the failure mode and the thickness of the sample. There is no effect of flaking on fracture surface morphology besides secondary cracks and local quasicleavage fracture.