Effectiveness of Different Reducing Agents during Sintering of Cr-Prealloyed PM Steels
Paper in proceedings, 2013

Development of strong inter-particle necks requires successful removal of surface oxides, present on the powder particles, during initial stages of sintering. In the case of water-atomized powder prealloyed with chromium, surface oxide is composed of mainly an iron oxide layer with some presence of more stable fine particulate oxides. Sufficiently strong inter-particle necks require as minimum full removal of the iron surface oxide layer. This can be achieved by a number of gaseous reducing agents (H2, CO or mixture of both) as well as by carbon typically admixed in the form of graphite. The present study is focused on the analysis of the reducing ability of the different sintering atmospheres (concentration of active gases ≤10 vol.%) and their combined effect with graphite by means of thermal analysis. Results indicate that the combination of the dry hydrogen-containing atmospheres and fine graphite grades allows successful sintering of chromium alloyed PM steels.

alloyed sintered steels

surface oxide

sintering atmosphere

reducing agent

oxide reduction.

Author

Eduard Hryha

Chalmers, Materials and Manufacturing Technology, Surface and Microstructure Engineering

Lars Nyborg

Chalmers, Materials and Manufacturing Technology, Surface and Microstructure Engineering

Proceedings EURO PM2013 Congress & Exhibition, 15-18 September 2013, Gothenburg, Sweden

Vol. 2 333-338

Driving Forces

Sustainable development

Areas of Advance

Production

Subject Categories

Other Materials Engineering

Metallurgy and Metallic Materials

More information

Created

10/7/2017