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为研究激光冲击强化(LSP)对镍基高温合金振动疲劳强度的影响,使用流水约束层和铝箔涂层,利用波长为532 nm,脉宽为10 ns,能量为1.5 J,冲击光斑尺寸为1.6 mm的YAG激光器对K417试件进行了激光冲击强化处理。使用升降法测试比较了冲击处理试件和未处理试件的振动疲劳强度。结果表明,试件经激光冲击强化后振动疲劳强度由106.5 MPa提高到285.5 MPa,疲劳性能大大提高。对激光冲击强化后的试件断口分析结果表明激光冲击的强化作用抑制了裂纹在试件表层的萌生和扩展,从而提高了材料的振动疲劳强度。
In order to study the influence of laser shock (LSP) on the vibration fatigue strength of nickel base superalloy, flow confinement and aluminum foil coatings were used. The wavelength of 532 nm, the pulse width of 10 ns, the energy of 1.5 J and the impact spot size of 1.6 mm YAG laser K417 specimens were laser shock-intensive treatment. The vibration fatigue strength of impact test specimen and untreated specimen was compared by using lifting test. The results show that the fatigue strength of the specimen increases from 106.5 MPa to 285.5 MPa after being strengthened by laser shock, and the fatigue performance is greatly improved. The analysis of the fracture surface of the specimen after the laser shocking shows that the strengthening of the laser shock can restrain the initiation and propagation of the crack on the surface of the specimen, thus improving the vibration fatigue strength of the material.