The results show that the thermal fatigue cracks after forming propagate preferentially in the hard phase, and the propagation of crack is stoped and dulled when it meet steel basic phase.
结果表明：萌生后的热疲劳裂纹优先在硬质相中扩展，遇到钢基体相后受阻、钝化。
The strength loss is greaser than the fracture toughness loss, because ofthe surface cracks caused. by thermal fatigue.
由于表面热疲劳裂纹的产生，使得材料强度性能损伤大于断裂韧性损伤。
The strength loss is greaser than the fracture toughness loss, because ofthe surface cracks caused. by thermal fatigue.
由于表面热疲劳裂纹的产生，使得材料强度性能损伤大于断裂韧性损伤。
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