High–temperature sintering of a hypereutectoid steel to theoretical density. (4th August 2014)

• Record Type: Journal Article
• Authors: Vollertsen, Frank
• Is Part Of: International journal of material & product technology. Volume 6:Number 4(1991)
• Page Start: 371
• Page End: 380
• Publication Date: 2014-08-04
• Subjects: powder metallurgy -- liquid phase sintering -- high temperature sintering -- reduction -- theoretical density -- hypereutectoid steel -- carbon monoxide -- densification optimisation -- alloys; Manufacturing processes -- Periodicals; Materials -- Testing -- Periodicals; 620.11
• Languages: English
• ISSNs: 0268-1900

Abstract

By using a hypereutectoid steel which develops a liquid phase during sintering above 1050°C the theoretical density can be achieved by a special high temperature sintering process. The limiting problem is the formation of carbon monoxide during the sintering process. If the carbon monoxide cannot escape due to closed porosity, further densification by rearrangement and solution reprecipitation cannot occur. The stress produced by the carbon monoxide in the pores is up to 2.7 MPa. So it is possible that there is an enlargement of the pores during sintering instead of pore shrinkage. An optimized densification to theoretical density can be achieved by a presintering process and low green density. The main sintering process lasts only 20 min, so low production costs are guaranteed. The alloy has excellent wear properties and high hardness.