Labrecque C.,Rio Tinto Iron and Titanium RTIT |
Cabanne P.-M.,Rio Tinto Iron and Titanium RTIT
69th World Foundry Congress 2010, WFC 2010 | Year: 2010
A foundry research project has been recently initiated at RTIT in order to better understand the fabrication of as-cast heavy section Dl parts meeting high impact energy requirements at low temperatures. The experimental castings have the following dimensions 180mm × 180mm × 190mm. The achieved as-cast Charpy impact strengths were as follows: 17 J ( R. T. ) ,16 J (- 20°C) and 11 J (- 40°C). The foundry process, the chemical composition and the microstructure of this experimental casting are compared to the ones of various examples in order to show the detrimental effects of residual elements, microshrinkage and microcarbide on the impact properties. Finally, quality index empirical models (based on casting chemical compositions) are used to analyse the impact tests results. This paper illustrates that an adequate nodule count can contribute to reduce the detrimental effects of the residual elements and microsegregation.