Ti/TiN/Zr/ZrN multilayer coating was deposited on lCrl7Ni2 martensitic stainless steel by vacuum cathodic arc ion plating. Rotary bending fatigue test was conducted at room temperature. The fatigue strength, fatigue life and fatigue fracture mechanisms of the coated and uncoated samples were investigated and compared. Such coating was of 11. 7 μm in thickness, 3 220 HV in hardness and 56 N in adhesion to the substrate. The results show that application of such coating to the steel substrate significantly increases the fatigue properties of the coated samples, in comparison with the uncoated samples. The fatigue limit can be increased by 11. 2% and the fatigue life of the steel can be increased between 108% and 246% when the samples were tested at stresses of the order of 540~650 Mpa. All the cracks initiate at the surface and the fracture process at low alternating stresses is dominated by the propagation of a single crack, whereas at elevated stresses many cracks can be observed. Main reasons for the improvement in fatigue properties can be concluded that the steel surface defect can be compensated by the coating to some degree, and the coating possesses high ability to impede the propagation of the cracks because of the special microstructure.%采用真空阴极电弧沉积技术在1Cr17Ni2马氏体型不锈钢表面沉积Ti/TiN/Zr/ZrN多层膜.研究对比了在室温下膜层试样与基体试样的旋转弯曲疲劳强度、疲劳寿命和疲劳断裂机理.结果表明:在不锈钢基体上沉积厚度为11.7 μm,硬度为3 220 HV0.025,膜/基结合力为56 N的Ti/TiN/Zr/ZrN多层膜后,其疲劳性能显著提高,膜层试样较基体试样的疲劳极限提高了约11.2％,当应力水平在540～650 MPa变化时,疲劳寿命增量变化范围为108％～246％;裂纹均起源于表面,在低应力水平下只有一个裂纹源,而高应力水平下有多个裂纹源；疲劳性能的提高主要是由于膜层能够弥补基体表面一定的缺陷,同时软硬交替的膜层结构有较强的抗裂纹扩展能力.
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