Stress Analysis of the Hard Disk with Overcoating Layer under the Contact with Head

헤드와의 접촉에 의한 오버코팅층을 포함한 하드 디스크의 응력 해석

Lee, Gang-Yong;Yang, Ji-Hyeok

  • Published : 2000.04.01


The purposes of the paper are to calculate stresses and strains of the disk with overcoating layer rotating quickly under normal loading and shear loading by contacting with head and to present material properties preventing the delamination between the disk and overcoating layer. The hard disk is modeled as two-layered disk composed with overcoating layer and the rest layers and the loading onto the disk is assumed axisymmetric. Solutions to equilibrium equations and compatibility equations are derived with the form of polynimial and Bessel function and coefficients satisfying boundary conditions are obtained differently for the case of body force, normal force and shear force. The risk of delamination are investigated for us to calculate the differences of strains at the interface between the disk and overcoating layer and the material properties preventing delamination are presented by calculating the differences of strains according to Young's modulus and density of disk.


Hard Disk;Stress Analysis;Overcoating;Function;Normal Loading;Shear Loading


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