Masahiro Anzai

Development of Large Ultraprecision Mirror Surface Grinding System with Elid

This paper introduces a new ultraprecision mirror surface machining system with ELID (Electrolytic In-Process Dressing). The machine has three linear axes, which can be controlled at a feeding resolution of 10nm under full closed feedback. 3-axes double hydrostatic guideway are used for sliding the machine, and hydrostatic bearing is used for the grinding wheel spindle. Ultraprecision mirror surface grinding, which achieved a surface roughness of 0.007 microns in Ra and surface straightness of 0.25 microns for a metal mold steel, was stably realized.

Fabrication of Ball End Mills for High Speed Milling and Their Cutting Characteristics

Ball end mills are regarded as indispensable tools for high speed milling. Especially, coated hard metal ball end mills are generally used for hardened steel cutting such as die and mold machining. There are several film generation methods and different film materials for the coating process that influence the cutting characteristics. At the same time, the adhesive strength between the coating layer and the base material is expected to increase so that flaking of the film can be reduced as much as possible and the tool cutting performance may rise. The study deals with the uniformity process of the cutting edge with magnetic field assisted polishing after tool grinding and before PVD TiAlN-coating. The magnetic field assisted polishing is expected to enhance adhesive strength, as well as achieving tool life improvement and machining stabilization. It is experimentally found that cutting tools treated by the proposed method show higher machining performance than untreated ones under high speed cutting conditions.

Fundamental properties of 3D microfabrication using a femtosecond laser

Micro scaled grooves and cavities are fabricated with the method of direct writing and superposing grooving in ambient air using femtosecond laser pulses and copper, aiming at establishing an industrially useful femtosecond laser processing machine to be able to fabricate three dimensional micro-scale structures, especially micro scaled molds, and processing techniques. The following items are demanded to make femtosecond laser processing machine an industrially useful tool. (1) There is no thermally influenced region around the area irradiated by the laser beam. (2) Surfaces irradiated laser beam are smooth. (3) Substances ablated to form are not attached on the surface of the work. In this study, fundamental properties of grooving and cavity processing are investigated experimentally, considering above items, especially eyeing on the items (1) and (2). As a result obtained in this research, the method of direct writing and superposing grooving havs a potential to fabricate micro scaled structure.