Membership Function Applied In Mechanical Structure Of The Theory Of Fatigue Damage Research And Application

In the paper, some basic problem in the theory of fatigue damage are discussed with the method of microcosmic and macroscopically, and with uniting the fatigue damage microcosmic theory and macroscopically fatigue experimentation to analyze fatigue damage of the metallic material and to summarize the fatigue characteristic parameter. According to the theory of fuzzy establish a new fuzzy cumulative damage model. Simultaneity, the effects of temperature and cyclic loads about the fatigue damage for metallic component are discussed. A corroding to the theory forecasting the life spans and establishes the fuzzy fatigue model for basic of the project application.Firstly, a corroding to the famous Miner theory, which analyze fatigue damage of the metallic component and establish the Miner model. But, in our practice, there is a difference between Miner model and fact. So, in the paper, analyze the damage relation between theory component and fact component by cycle loads, and define a new conception what inertia damage is, establish a new model what is fuzzy fatigue damage model, establish a new coefficient what is fatigue membership, Which approve that the difference exist between the real damage and theory damage in our paper, and supply a basic theory model for analysis the lifetime.Secondly, in the paper, this based on 16MnR alloy and through the experiment to take the mechanic parameter. Analyze fatigue damage characteristic of the metallic welded joint according to the metallic fatigue damage result and welded joint characteristic. Establish a new damage parameter, a new fuzzy fatigue damage life-span model of welded joint, and analyze the fatigue damage theory of the metallic welded joint by metallography.