Design And Experimental Research Of An In Situ Tensile-torsion Mechanical Testing Device

The research of the mechanisms of the material injury and deformation in particularsituation has a significace in the demanstraion of their service，reliance and theassessment of shelf-life. It is a research that meets a considerable number of needs andbe clearly proposed in the natioal long-term technology development strategy. Thiswork is also the hotspot of academia. In this paper, an in situ tensile-torsion device ispresented which can be made under the microscope dynamic monitoring the materialinjury situation. With this device, a series of experimental studies were carried out toget the law of plastic material during tensile-torsion tests. Explore the law throughfurther in-situ optical microscopy experiments, and fully demonstrate macrophenomena from the point of microscopic.The essay starting from the basic principles complete the disignment of the testequipment,at the same time summarize the method of the miniaturization of complexload summary situ testing device and make a necessary explanation of the work of theelectrical control system and the software applying on it. Combined the work of designand analysis, a series of research of testing and error analysis are conducted in terms ofthe testing device.As a significant role of the design work of the in situ tensile-reversestress testing device, the establishment of the experiment and theory matrix has abenefit for quantifying the error and then propose effective error correction algorithm.Applying the device of proposed in this essay in the stretched-torsional compositeload test effectively reveals the interaction of two stresses in the plastic materialdeformation process, especially in the test of the typical metal materials. Also, thestretch-torsion testing based on in-situ optical microscopy analysis is carried out.Through the test and analysis of the differences and changes of microstructure in thethree load forms--pured twisting, pured stretching and twisting-stretching, therelationship between the microstructure and macroscopic correspondence can be explained. At last.the results of the microstructure in situ test are used to demonstrateand explain the results of the complex load-form mechanicaltest.Research work of this paper covers the design, manufacture, assembly and testing ofthe device. Based on it, the experiment is carried out. And then testing and analysis areconducted on the materials. The influence is presented between tessile and torsion ofplastic materials under large deformation. By analyzing the microstructure, therelationship between the performance characteristics of the material microstructure andunder complex loading is explained. It is of great significance for revealing materialmicrostructure and macroscopic properties.