Patent ID: 7420886

Claim:
A thermal stability measuring method of a magnetic recording medium, the method comprising the steps of: disposing the magnetic recording medium constituted by forming at least a magnetic layer on a substrate, and a magnetic head comprising a read/write element provided with a read element and a write element fixed to one end of a head support member on the main surface of the magnetic recording medium under an atmosphere heated to a predetermined temperature; relatively moving said magnetic head with respect to said main surface, and writing a signal to a predetermined track position on said magnetic layer by said write element; and detecting the write signal written to said track by said read element, and comparing said write signal with said detected signal to calculate the signal attenuation of the magnetic recording medium to measure the thermal stability of the magnetic recording medium, wherein: the write track width of said write element is set to be larger than the total of the track width of a radial direction of said track position on said magnetic layer, and the movement amount of said track position in the radial direction by thermal expansion caused by heating said head support member.