Research on Failure Mechanism of Abrasive Belt and Effect on Sanding of Medium-Density Fiberboard (MDF)

Sanding is a very important process in MDF production. In this study, abrasive belts (P60 and P120) and MDF were used to conduct sanding experiments, and mass variation, surface morphology, and surface roughness of the abrasive belts were measured to analyze the failure process of the utilized abrasive belts. It is found that the mass of the abrasive belt mainly increased in the sanding process. The increase range of P60 is mainly within the scope of 0~0.02 g, while for P120, the mass change mostly fluctuates within 0~0.01 g. The surface roughness (Sa and Sku) of abrasive belts presents a down-and-up trend as sanding times increase, and Sa and Sku of P60 are both larger than those of P120. Wood fibers with adhesive blocked the space among grits and led to a “grits gathering” phenomenon. When the area of “grits gathering” is larger, it forms an abrasive belt “blocking”. Grit wear (dropping-off, fracture) and “blocking” constitute the two predominant patterns of the failure mechanism. This study is helpful to further improve wood-material-sanding theories, provide insights to investigate wear forms of other abrasive belts, and determine and extend the life of abrasive belts.