Effects of chromium sources on the microstructure and properties of TiC-steel composites

ABSTRACT

The composites of low alloy steel reinforced with TiC particles (36 wt-%) were prepared by conventional powder metallurgy process in this paper. The chromium in the steel matrix was provided by pure chromium powder (PCP), low carbon ferrochrome powder, medium carbon ferrochrome powder (MCFP) and high carbon ferrochrome powder. The SEM was used to observe the particle morphology and microstructure. Density, hardness and transverse rupture strength (TRS) of the samples were tested. The results show that the composite prepared with the PCP as a chromium source has low hardness and TRS and the composites prepared with different ferrochrome powders have higher hardness and TRS. The microstructures of the samples prepared with different chromium sources have some differences and provide the differences in mechanical properties and fracture morphology. The sample prepared with the MCFP as chromium source has the highest comprehensive performance after tempering: hardness 70 HRC and TRS 1752 MPa.

KEYWORDS:

• Metal matrix composite
• titanium carbide
• chromium
• cermet

Disclosure statement

No potential conflict of interest was reported by the authors.

Notes on contributors

Tao Lin is a professor of Institute for Advanced Material & Technology, University of Science and Technology Beijing, Beijing, People's Republic of China. He has extensive experience in field of powder metallurgy. He is mainly engaged in hard materials and coatings, tungsten and tungsten alloys, and powder metallurgy friction materials.

You Guo is a master graduated from Institute for Advanced Material & Technology, University of Science and Technology Beijing, Beijing, People's Republic of China. He is mainly engaged in the study of metal matrix composites.

Zhi Wang is a doctorgraduated from Institute for Advanced Material & Technology, University of Science and Technology Beijing, Beijing, People's Republic of China. He is mainly engaged in the study of metal matrix composites.

Huiping Shao is a professor of Institute for Advanced Material & Technology, University of Science and Technology Beijing, Beijing, People's Republic of China. He has extensive experience in field of powder metallurgy. She mainly studies in the fields of gel injection molding medical porous implant materials, intelligent damping damping, dynamic seal, target biological magnetic materials, powder metallurgy and other fields.

Haiyang Lu is a student of Institute for Advanced Material & Technology, University of Science and Technology Beijing, Beijing, People's Republic of China. He is mainly engaged in the study of metal matrix composites.

Xinbo He is a professor of Institute for Advanced Material & Technology, University of Science and Technology Beijing, Beijing, People's Republic of China. He has extensive experience in field of powder metallurgy. He is mainly engaged in the research and application of powder metallurgy metal matrix composites, new electronic packaging materials and high temperature ceramic matrix composites.