Innovative Casting Process Simultaneously to Achieve Sintering of Ceramics and Joining of Metals and Ceramics

2020 Fiscal Year Final Research Report

• Project/Area Number: 19K15332
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 26060:Metals production and resources production-related
• Research Institution: Akita University
• Principal Investigator: Goto Ikuzo 秋田大学, 理工学研究科, 講師 (10632812)
• Project Period (FY): 2019-04-01 – 2021-03-31
• Keywords: 焼結 / 酸化接合 / チタン酸バリウム / 純アルミニウム / 接合界面 / アルミナ / 鋳造

Outline of Final Research Achievements

The pressing behavior of barium titanate powder and the sintering behavior of the green pellets were examined. The possibility of the process conditions simultaneously to achieve both the sintering and the joining of pure aluminum and the sintered barium titanate. For the uniaxial pressing behavior, excessive pressing pressure leads to decrease in density of the green pellets. For the pressureless sintering behavior of the green pellets produced by mixing different powder with particle sizes of 1μm and 25nm, high content of the powder with particle size of 25nm also leads to the increase in density of the sintered compacts. In addition, the holding of the contact between the green pellets and pure molten aluminum under the sintering condition caused the interfacial joint due to the generation of intermediate alumina layer. These results suggest that the sintering and the oxidation joining can be simultaneously achieved within a short time.

Free Research Field

鋳造工学

Academic Significance and Societal Importance of the Research Achievements

本研究の目的は，金属の鋳造による成形と同時にセラミックスの焼結・金属とセラミックスの接合を行う革新的プロセスを実現することである．これまでの研究を通じて，高温保持により純アルミニウム溶湯とチタン酸バリウムの界面にアルミナ層を形成させることで，冷却・凝固後に接合が得られることを明らかにした（酸化接合）．これには，少なくとも780℃では24時間以上の接触保持が必要であったが，1000℃以上の高温下で酸化を促進することにより短時間で接合が得られることを示すことができた．さらに，この過程でチタン酸バリウムの焼結も同時に行うことによる高効率な鋳造接合プロセスの実現性を示すことができた．