The relation of law of the fatigue crack extending and feature of macro-profile is discovered,which provides a new method for the life estimation of the brake disc.

• 发现裂纹剖面宏观形貌特征与制动盘疲劳裂纹扩展规律之间存在一定的关联,为制动盘寿命评估提供了新的思路。