Fabrication and Application of Gel Forming Ultrafine Diamond Abrasive Tools

Abstract

To solve the problem of phase agglomeration and microstructure inconsistency in the conventional powder pressing method of ultrafine diamond abrasive tool, a fabrication method of ultrafine diamond abrasive tool based on gel forming was proposed. The gel experiments of polyvinyl alcohol (PVA) and phenolic resin (PF) were carried out, and the basic physicochemical properties of the gel were tested by SEM, IR and TGA. The mechanical properties of gel forming and hot pressing forming abrasive tools were Compared. The polishing experiments of the gel abrasive tool and the hot-pressing abrasive tool were carried out. The results showed that when the PF/PVA ratio was between 5:1 and 10:1, the porous network gel structure was formed. The IR and TGA analysis indicated that the molecular crosslinking of PF and PVA occurred after gel. Compared with hot pressing abrasive samples, the abrasive distributions of gel abrasive samples were more uniform. The supersmooth surface of the SiC flat mirror with surface roughness Ra below 3 nm was obtained by the gel abrasive tool, which was better than by hot pressing abrasive tool. The surface flatness value PV 0.213 μm could be obtained by using the gel abrasive tool with low PVA content.

The Preparation and Performance Analysis of a Cr2O3 Gel Abrasive Tool for Sapphire Substrate Polishing

“…Niu et al [15] proposed a method to process BK7 glass by a vitrified bondfixed abrasive tool formed by the combination of a precision diamond abrasive and a coarse diamond abrasive. Feng [16][17][18] proposed a Polyvinyl alcohol/phenolic resin (PVA/PF) composite sol-gel tool to process SiC wafers. The abrasive tool showed excellent processing stability during processing.…”

Study on Development of Composite PAM/PI Gel Abrasive Tools and Finishing Performance on the Sapphire Substrates

“…Lu 11 proposed a diamond abrasive gel abrasive with a silicon oxide coating on the surface, which was found to improve the surface quality and the MRR in processing silicon carbide Xu 12 et al prepared the abrasive tool through sol-gel method. Feng [13][14][15] prepare the gel abrasive tool, which uses phenolic resin and polyvinyl alcohol as the bonding agent to machine the SiC wafer. The abovementioned methods address the problem of the agglomeration of the inorganic particles, but some of the binding agent is not universally utilized and the thermal resistance of some tool is poor.…”

“…(4) Place the gel body in the oven and raise the temperature to 350 °C then cool it slowly to room temperature to get the abrasive tool. The fabrication method of hot-pressing Cr 2 O 3 abrasive tool is adopted from reference 15 and the specific preparation process is: (1) Mixing the powder (2) Drying at 70 °C (3) Molding and then sintering at 350 °C. The bonding agent used in the hot-pressing abrasives is PI resin, other contents of the hot-pressing tool is same as the gel abrasive tool.…”