Formation of c-Axis Aligned Polycrystal Hydroxyapatite Using a High Magnetic Field with Mechanical Sample Rotation

Abstract

  It is possible to control the crystal alignment of non magnetic materials such as anisotropic ceramics and polymeric materials using a high magnetic field. However, alignment of the c-axis direction in hexagonal crystals, with a magnetic susceptibility of χ_c<χ_a=χ_b, is uncontrollable under a static magnetic field, because the c-axis can be in arbitrary direction in the plane perpendicular to the direction of the magnetic field. In this study, a high magnetic field and mold rotation are simultaneously imposed on a sample in order to align crystals parallel to the c-axis that has small magnetic susceptibility. This process was applied to hydroxyapatite crystals and a sample, in which the c-axis of the crystals aligned in a particular direction, was successfully obtained.