Design And Experimental Research Of An In Situ Tensile Device For Characterizing Micro-mechanics Of Materilas At Middle/low Frequencies

The mechanical property of materials is an important factor could decide the usability,durability and reliability of manufactured goods. It directly impacts a nation’s materialsproducts quality level, such as ferrous metallurgy, non-ferrous metal etc. Material technologyis the basic of a country’s national economy, therefore to a great extent, the testing level andsupport capacity of material mechanical property also effect the overall level of hightechnology industry cluster, such as device manufacturing industry, national defense military,aerospace etc. so the research of material mechanical property always attacks people’sattention. With the development of the microscope technology， through researches peoplefound that the change in material micro structure could directly effect material macro structuremechanical property， while through existing test device we could not acquire materialmechanical property data and obtain its micro structure change simultaneously.As to above problems， in this paper， a set of in situ observation device suit for low andmedium frequency material micro stretching based on a sort of high resolution，high scanningrate observation device is researched， it could realize mechanical property test and in situobservation， such as modulus of elasticity， fracture strength， limit of yielding and so on.Main research contents include: firstly，design and processing a set of test device suit forlow and medium frequency material micro stretching test. The device includes precisiontransmission element， signal acquisition element and low frequency drive element;Secondly， making several stretching experiments aim at different shape， structure ofspecimens through this device， making a comparison between the result and material relativeparameter， Identification device feasibility; Making repeated test， Identification devicereliability. The analysis of experimental results and data indicate that through this device wecan take tests aim at material mechanical property in material stretching process，simultaneously we could research material micro structure change in the stretching processthrough microscope; Finally， making several low frequency stretching experiments throughthis device， in situ observing through microscope， analyzing the low frequency stretching effects on material elastic stage， Strengthening stage and necking stage， provide a referencefor analyzing material fatigue properties.