Research And Development Of The Tensile Fatigue-testing Machine And Fatigue-test System Used For Measuring The Heat Dissipation

It's called fatigue that in engineering structures crack is generated and propagated and leads to fracture due to withstanding fluctuating load. Research in fatigue property helps with predicting the fatigue lifetime and the fatigue test is an effective means to acquire numerous data on fatigue property. It comes out that the fatigue machine is a necessary device in the research of fatigue property, which is widely used in quality test, measurement examination and experiment study to be an important testing device.The content of this paper includes:researching a new control and mechanical system design of the fatigue machine used for tension test; designing a special station for this fatigue machine; designing a special station of detecting energy; proposing a new method of detecting accumulated energy and establishing a model for predicting the fatigue lifetime and fatigue residual lifetime.First, based on the principle of innovation design, this paper establishes a functional structure and forms a new fatigue machine design after resolving function, integrating principles and selecting principles.Secondly, this paper researches the control and mechanical system of the fatigue machine and designs the structure of the hardware and software for the control system. For the mechanical system, this study designs the mechanical structure, checks the screw drive, uses COSMOS for modal and static analysis and uses ANSYS to simulate the fatigue situation under constant amplitude loading and random loading. A fatigue machine for bumper is proposed as a case to show the application.At last, this study gives an experimental method for testing the accumulated energy based on the energy approach of fatigue theory. On this basis, a special device for testing energy is designed and to be integrated with the fatigue machine. This study researches the relationship among storage of materials, fatigue strength, tensile strength, fatigue lifetime and fatigue residual lifetime. The mathematical model of temperature and residual lifetime based on the experiments is described in detail.