摘要To study the conservative life of the artificial mechanical heart valve holder, CATIA software was used for modeling, and ABAQUS finite element analysis was used to analyze the stress of the valve holder in the complex environment of the human body and the residual thermal stress during production and processing. The damage tolerance method based on fracture mechanics analyzes the maximum initial crack size that the heart valve holder can tolerate under the premise that the structural safety life is longer than the life of the implanted patient. The results show that the maximum initial crack size is only tens of microns; the traditional S/N life analysis can only obtain non-conservative life, and the damage tolerance method is the basic requirement for analyzing the life and quality control of artificial mechanical heart valves.
Abstract：To study the conservative life of the artificial mechanical heart valve holder, CATIA software was used for modeling, and ABAQUS finite element analysis was used to analyze the stress of the valve holder in the complex environment of the human body and the residual thermal stress during production and processing. The damage tolerance method based on fracture mechanics analyzes the maximum initial crack size that the heart valve holder can tolerate under the premise that the structural safety life is longer than the life of the implanted patient. The results show that the maximum initial crack size is only tens of microns; the traditional S/N life analysis can only obtain non-conservative life, and the damage tolerance method is the basic requirement for analyzing the life and quality control of artificial mechanical heart valves.
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