Polishing solution for hard disk magnetic head and preparation method thereof

Abstract

The invention discloses polishing solution for a hard disk magnetic head and a preparation method thereof. The polishing solution is mainly prepared from diamond abrasive particles, a dispersing agent, a corrosion inhibitor, a phase transfer solvent, an oil phase medium regulator and a hydrocarbon solvent, wherein the average particle size of the diamond abrasive particles is 30 to 150nm, the particle size distribution of the particles is 20 to 300nm, and the length-diameter ratio of the particles is 1.0 to 2.0. The preparation method comprises the following steps of: mixing diamond powder and a surface modifier, grinding, removing impurities, and grading to obtain suspension slurry; adding the phase transfer solvent into the suspension slurry, and stirring and dispersing the system; removing fine particles and coarse particles in the phase transfer solvent system by grading to ensure that the particle size distribution and concentration of the diamond abrasive particles meet the requirements; and transferring to the hydrocarbon solvent, adding the oil phase medium regulator, the dispersing agent and the corrosion inhibitor, and uniformly stirring to obtain the polishing solution for the hard disk magnetic head. The polishing solution prepared by the method has high suspension stability and dispersion uniformity, and high polishing efficiency during polishing, and a machined surface has high quality.

Description

technical field [0001] The invention belongs to the technical field of ultra-precision grinding and polishing treatment, and in particular relates to a magnetic head polishing liquid and a preparation method thereof. Background technique [0002] With the increase of hard disk storage density, the recorded magnetic signal line width has reached the nanoscale, the actual flying height of the magnetic head is less than 4nm, the surface roughness of the magnetic head must be less than 0.2nm, and the surface processing accuracy of the components must reach the sub-nanometer level. In order to improve the processing efficiency, reduce the roughness of the magnetic head, and eliminate the fatal damage caused by scratches and impurities embedded in the magnetic disk, it is necessary to develop a high-quality polishing fluid suitable for ultra-precision processing of the magnetic head of a high-storage-density hard disk. [0003] As an excellent abrasive, diamond has always been one...

AI Technical Summary

Problems solved by technology

In the existing preparation method of magnetic head polishing liquid, it generally uses 3nm to 18nm nano-diamond as abrasive grains, which can cause particles to be on the surface of the blank when the abrasive grains are used for magnetic head polishing (especially for compact compact abrasive polishing). Defects in the holding force cause the abrasive grains to fall off easily during the polishing process, and the cutting rate drops sharply. At the same time, the fallen abrasive grains tend to form black spot defects on the surface of the magnetic head, resulting in a significant increase in the defective product rate

In addition, in the preparation process of the existing magnetic head polishing liquid, the process of crushing and then drying is often adopted. Due to the high surface energy of the nano-powder particles, it is very easy to form hard agglomerates during the drying process, making the particle size of the diamond powder in the actual system and morphology cannot be effectively controlled, and the problem of particle dispersion cannot be effectively solved accordingly.

Since the dispersion and stability of existing nano-diamond powders in the system have not been effectively solved, the powders often exist in the form of agglomerates, and the actual abrasive grains have irregular shapes, inconsistent sizes, and poor bonding between crystallites. Strong, prone to chipping under loading conditions, resulting in easy scratches and black spots during polishing, so the quality of head polishing will be unavoidable