1. Field of the Invention
This invention relates to an apparatus for evaluating the mechanical properties of materials that can evaluate the mechanical properties of a test specimen in magnetic fields of two different orientations.
2. Description of the Prior Art
In superconducting generators, superconducting magnetic energy storage devices, linear motors and other such superconducting device technologies, the importance of the relationship between the mechanical properties and the magnetic field orientation of superconducting materials and structural materials is such that prior evaluation of this relationship is required. However, the difficulty of making an apparatus for evaluating data relating to the mechanical properties of such materials has meant that the amount of such data that has been collected is insufficient.
In a conventional apparatus for evaluating the mechanical properties of a material in a magnetic field, a test specimen is placed in a superconducting magnetic field and subjected to a load while the strength of the material under the load is evaluated. Such apparatuses for evaluating the mechanical properties of a material having a unidirectional magnetic field orientation have already been announced. For example, on page 119 of the proceedings of the 45th meeting on Cryogenics and Superconductivity of the Cryogenic Association held in the spring of 1991, a system arrangement is shown in which a solenoid type magnet in which a relatively high magnetic field can be readily generated is used to apply a load in order to evaluate the properties of a material in a magnetic field oriented in the same direction as that of the direction in which the load is applied.
However, while a solenoid type magnet can be used to evaluate the mechanical properties of a test specimen in a unidirectional magnetic field, the magnetic field orientation cannot be changed. This makes it impossible to evaluate the mechanical properties of a material under different magnetic field orientations, and as such makes it inadequate for evaluating the mechanical properties of materials that are to be used in fields relating to superconduction technology. While for the purpose of evaluating the mechanical properties of a material in different magnetic field orientations a separate superconducting magnet may be provided to generate a magnetic field in a different direction, such an arrangement would require the provision of at least two superconducting magnets, which would thereby increase the size and cost of such an apparatus.