Abstracts and Available Papers Presented at the
2003 International RERTR Meeting

Development of the Fabrication Technology for a HANARO Fuel Rod by the Indirect Extrusion Method

Jong-Man Park, Ji-Young Eom, Jong-Yeob Jung, Young-Mo Ko, Geun-Sik Joo

Chong-Tak Lee, Chang-Kyu Kim, Dong-Seong Sohn

Korea Atomic Energy Research Institute
150, Dukjin-Dong, Yuseong-gu, Daejeon, 305-353, Korea

ABSTRACT

In order to get basic data for the developing of a new fabrication process for a HANARO fuel rod, extrusion characteristics by using the direct and in-direct extrusion methods were investigated with extrusion billets composed of a dummy fuel core and an aluminum can as functions of the temperature, conical angle of the die, green density of the fuel compaction, and the shape of the core compact. In the case of in-direct extrusion, the cross section at the middle of the fuel rod showed a closely octagonal shaped core with a constant cladding thickness. However, at both the front and rear end parts of extruded fuel rod, imbalances existed in the cladding thickness as well as a penetration of Al into the fuel core of extruded rod. It is of note from the result that the variables such as extrusion temperature, conical angle of the die, and green density of the fuel compact did not effect significantly the degree of imperfections in the extruded fuel rod, but the imperfections were improved greatly by changing the shape of the core compact in the extrusion billet. Direct extrusion appeared to have no advantage for improving the imperfections due to a severe fluctuation of the metal flow between the fuel core and cladding material.