EBSD study to analyse mechanisms of phase boundary and grain boundary development in WC-Co cemented carbides

ABSTRACT

A systematic characterisation of the boundary structure in WC-Co cemented carbides was made as a function of the cobalt content and carbon potential using electron backscattered diffraction technique, with the aim to analyse the mechanisms of WC/Co phase boundary and WC/WC grain boundary development. The fraction of grain boundaries with basal or prismatic habit planes was estimated using a stereological method. Special grain boundaries were classified as a function of the rotation axis between adjacent grains. Although a few special grain boundaries originate from the powder, most grain boundaries form during heat treatment. The development of grain boundaries and phase boundaries during sintering is discussed from the results. The surprising lack of variation in the distribution of boundary types over large changes in volume fraction and composition is particularly commented. Finally, a mechanism of cooperative migration of grain boundaries and phase boundaries is proposed to explain microstructural observations associated with grain growth.

KEYWORDS:

• Cemented carbides
• EBSD
• grain boundary
• phase boundary
• interface
• sintering
• grain growth

Disclosure statement

No potential conflict of interest was reported by the authors.

Notes on contributors

Maxime Pellan is currently an application engineer at Sandvik Hyperion. He received his M.S. and PhD degrees in Material Science and Engineering at Grenoble INP, Univ. Grenoble Alpes, France.

Sabine Lay is currently a CNRS senior researcher at Grenoble INP, Univ. Grenoble Alpes. She received her M.S. and Ph.D. degrees in Materials Science and Engineering at University of Caen, France.

Jean-Michel Missiaen is currently professor at Grenoble INP, Univ. Grenoble Alpes. He received his M.S. degree in Materials Science and Engineering at University of Caen, France and his PhD degree in Materials Science and Engineering at Grenoble INP, Univ. Grenoble Alpes, France

Susanne Norgren is currently group expert at Sandvik and also adjunct professor at Uppsala University. She received her M.S. and Ph.D. degrees in Department of Material Science at The Royal Institute of Technology, (KTH), Sweden.

Jenny Angseryd is currnetly global EHS manager at Sandvik Hyperion. She received her M.S at the Department of Material Science, Royal Institute of Technology, (KTH), Sweden and Ph.D. degree at the department of Applied physics, Chalmers university of technology (CTH), Sweden.

Ernesto Coronel is currently Specialist, Materials Characterization at Sandvik Coromant. He received his M.S. and PhD degree at the Department of Applied Material Science, Uppsala University, (UU), Sweden.

Tomas Persson is currently a R&D Specialist at Seco Tools AB. He received his B.S. and M.S. degrees in the Department of Material Science and Engineering at KTH Royal Institute of Technology, Sweden.

ORCID

Susanne Norgren http://orcid.org/0000-0003-1471-8307

Tomas Persson http://orcid.org/0000-0001-8552-8290

Jean-Michel Missiaen http://orcid.org/0000-0002-1318-4772