某镍钛合金医疗器械产品，在疲劳测试过程中发生早期断裂失效。通过扫描电镜及能谱仪等对产品断裂原因进行了分析。结果表明：产品发生早期断裂失效是由于其原材料多股丝表面存在机械抛光凹陷，降低了材料的疲劳抗力，致使产品在周期性疲劳应力作用下发生了早期疲劳断裂失效；严格控制产品原材料表面质量，是提高镍钛合金丝材产品疲劳抗力的重要途径。

Early fracture failure of a nickel-titanium alloy medical device product occurred during fatigue testing. The fracture causes of the product were analyzed by scanning electron microscope and energy spectrometer. The results show that the early fracture of the product was due to the mechanical polishing hollow on the surface of the multi-stranded wire of the raw material, which reduced the fatigue resistance of the material and caused the early fatigue failure of the product under the action of cyclic fatigue stress. Strictly controlling the surface quality of the raw material is an important way to improve the fatigue resistance of the nickel-titanium alloy wire products.