Diamond lapping is generally used as a shape creation method for advanced single-crystal substrates for electronic devices. However, a deep damaged layer is formed at the substrate surface in this process. The depth of this damaged layer affects the cost of the whole process. Here, a novel damage-less and high-efficiency mechanical polishing technique for advanced crystal substrates using a resin pad and electric field assisted polishing is proposed. This novel mechanical polishing method was compared with conventional diamond lapping with sapphire as the substrate. The mechanical polishing method using a resin pad reduced the damaged layer depth by approximately 0.16 times compared to the conventional process using a Cu platen. In addition, the removal rate was increased by 1.5 times by applying electric field-assisted polishing in comparison with the conventional lapping technique using a platen 910 mm in diameter.

A fine lattice coating system was developed that applies a functional porous structure to the surface of bulk material based on metal additive manufacturing with a laser beam. Here, we propose a powder supply method with gravity fall, and examined the surface profile of the top layer when printed using this method. The results indicated that the top surface of the printed structure became smooth when the printing process exceeded a certain layer depending on the powder supply deposition state. In addition, the wall structure printed by the method could be formed up to a height of 0.4 mm in the upright state, indicating the effectiveness of printing by the powder supply method with gravity fall.

This paper clarifies the creep feed grinding mechanism from the grinding forces acting on a single-grain cutting edge. A highly responsive piezo electric type dynamometer was manufactured and a grinding wheel was made with longer successive cutting edge distance than arc contact length. Single-grain grinding experiments were carried out and the grinding force components were measured. The force ratio increased with small grain depth of cut area in up-cut grinding experiments suggesting the occurrence of rubbing or plowing. Rubbing and plowing were suppressed with down-cut grinding using the grain cutting edge formed by the flattend area and the microfractured area.