Machining of Single‑Crystal Sapphire with Polysaccharide‑Bonded Abrasive Tool

A novel polysaccharide-bonded abrasive tool is proposed for the green machining of single-crystal sapphires.The prescription and manufacturing process of the proposed tool is designed,and the gelation property of polysaccharide by microwave treatment is investigated.Abrasive tool samples are fabricated,and a machining experiment on a single-crystal sapphire is performed.It is found that the crystallinity of polysaccharide gel decreases as the proportion of cross-linked polysaccharide increases.Abrasive tool samples with cross-linked polysaccharide present higher surface hardness.With the new abrasive tool,the surface quality of sapphire wafer can be significantly improved.This new tool with an abrasive to binder ratio of 2∶1 attains a material removal rate of 0.68μm/min.It is found that increasing the abrasive to binder ratio leads to better self-dressing performance but worse material removal ability and greater loss of abrasive tool materials.The validity of polysaccharide as an abrasive tool binder is preliminarily verified.

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