Research on microstructure and high-temperature friction and wear properties of a cobalt-based alloy for hot extrusion die

• Published in: Baosteel Technical Research Vol. 14; no. 1; pp. 8 - 18
• Main Authors: Qu, Haixia, Tang, Chenglong, Gu, Tingquan
• Format: Journal Article
• Language: English
• Published: Shanghai Baosteel Technical Research 01.03.2020; Research Institute, Baoshan Iron & Steel Co., Ltd., Shanghai 201999, China
• Subjects: Alloys; Cemented carbides; Cobalt base alloys; Extrusion dies; Friction; High temperature; Hot extrusion; Impact strength; Impact tests; Investigations; Microcracks; Microstructure; Powder metallurgy; Scanning electron microscopy; Surface properties; Titanium carbide; Wear resistance; Working conditions; hot extrusion die; cobalt-based alloy; microstructure; high-temperature friction and wear properties
• ISSN: 1674-3458
• DOI: 10.3969/j.issn.1674-3458.2020.01.002

The hot extrusion die is a key tool for determining the surface quality and dimensional accuracy of extruded products. Because its service process is subject to high temperature,high pressure, and wear,it must be resistant to these conditions. In this paper,the high-temperature friction and wear properties of a cobalt (Co)-based aioy were investigated and compared with those of a titanium carbide (TiC) cemented material. The results show that the high-temperature wear performance of the Co-based aioy is better than that of the TiC cemented material, and that Co-based materials have the potential for replacing TiC cemented materials as hot-extrusion-die materials. Due to the high density and good combination of the matrix and carbide,the carbides do not easily peel off from the matrix during the wear process. Due to the higher impact toughness of the Co-based alloys, microcracks that can cause worn-surface peeling are not easily generated. As a result,the high-temperature wear performance of Co-based aioys is found to be better than that of TiC cemented materials.