Experimental Investigation Into The Constitutive Relationship Of 2A12 Aluminum Alloy

The constitutive relations of materials, especially dynamic plastic constitutive relations, have always been one of the emphases in mechanical and material fields. The 2A12 aluminum alloy, used in aerospace and military field, is commonly accepted due to its low density and high yield. With the development of computer and method of numerical calculation, numerical simulation has become an important measure in studying engineering, while dynamic constitutive relations of materials is still an obstacle astricting its development. There is no data serving for mechanics character of home-made 2A12 aluminium alloy in store depot of common numerical simulation soft of AUTODYN . There is no other way but taking near component 2024 aluminium alloy made in U.S. as substitution which will have effect on experimental result. As a result, it is vital to investigate dynamic mechanics behavior in impacting load under normal and high temperature, and then find its constitutive relations.Firstly, this paper gives an outline of constitutive relations of materials. Material strain in the phases of plastic distortion is not only related with stress, but also affected by loading history and strain rate, as well as temperature. Johnson-Cook material strength model can depict domino effect of material strain harden, strain-rate harden and temperature soft. It is a constitutive equation common used in metal and alloy material, even is widely used in numerical simulation soft of AUTODYN.Secondly, this paper clarifies the essence of experimental method of SHPB compression bar according to transmitting theory of one dimension stress wave. The paper also designed and made a heating electric stove and an apparatus for measuring temperature, and expatiate principles of the latter. With the apparatus, distribution curve of temperature along the axis in the heating electric stove can be measured, and the length of constant temperature area can also be confirmed. As a result, the paper testifies that the experiment can ensure homogenization of temperature in test pieces. The paper also discusses the problem of demarcating strain gauge and gets the conclusion that deviation is less in demarcating...