Development of high-efficiency, high-quality machining technology for sintered carbide by grinding with electrolytic action

2020 Fiscal Year Final Research Report

• Project/Area Number: 18K03884
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 18020:Manufacturing and production engineering-related
• Research Institution: Shizuoka Institute of Science and Technology
• Principal Investigator: Goto Akihiro 静岡理工科大学, 理工学部, 教授 (00711558)
• Project Period (FY): 2018-04-01 – 2021-03-31
• Keywords: 電解 / ミーリング / 超硬合金

Outline of Final Research Achievements

As a high-speed and high-precision machining method for sintered carbide, we have developed a grinding method that utilizes electrolysis. This is a method in which Co is eluted by electrolytic action and the fragile sintered carbide is scraped off with insulating abrasive grains.
The reaction of the surface due to the electrolytic action was investigated. It was found that the ionization and elution of Co, which is a component of sintered carbide, occurs first, followed by the reaction of WC oxidation. In the actual machining test, it was shown that the machining load can be reduced when the electrolytic reaction was used.
In addition, assuming materials containing Cr will be machined, we conducted research on hexavalent chromium formation prevention technology. By supplying divalent iron ions into the electrolyte, the phenomenon of hexavalent chromium formation could be suppressed.

Free Research Field

電気加工

Academic Significance and Societal Importance of the Research Achievements

ものづくり現場では、機械部品を精度よく、安価に大量に作るための方法として、冷間鍛造金型を超硬合金化することが注目されている。しかし硬質材料であるため、加工が困難であり、広い普及には至っていない。超硬合金の高速高精度な加工方法として、研削加工に電解加工の作用を複合させることで、加工効率を高めることができるようになり、超硬合金を使用する問題の一つを解決できると考える。また、電解作用を利用する際に問題になる六価クロム生成の問題についても、解決する方法を提供することができるようになると考える。