Papers by Keyword: Cladding Materials

Abstract: Currently, Zr-alloys are widely used in nuclear power reactors for fuel cladding and structural components. Many types of zr-based alloys were developed to overcome the challenges encountered in the progress of nuclear reactors (high-burnup and high-duty). Oxygen diffused into the cladding, hydrogen absorbed in the cladding (breakaway oxidation and ruptured balloons) and rapid oxidation rate are results of chemical interaction of cladding material with steam at high temperature. Zirconium alloys seem to be the most suitable for use in fuel cladding, if they can overcome the rapid oxidation at temperature higher than 1200 °C. Previous studies on the oxidation behavior for some Zr-alloys nuclear fuel cladding tubes in steam and steam–air atmospheres at high temperatures are reviewed. The oxidation behavior of zirconium-alloys is strongly affected by the chemical composition of alloys and its surface conditions.

Abstract: Thermal shock properties of Q235A steel used ternary-boride-based (TBB) cladding material has been studied. The result indicates that this cladding material has excellent resistance to thermal shock and that the cracks are not difficult to occur at the interface of cladding layer and steel substrate. The mechanism of thermal shock failure is fatigue failure brought by cycle stresses. The thermal shock has little influence on the hardness of cladding layer. The structure of cladding layer has no obvious change after the thermal shock, but the phase of steel substrate change from ferrite and pearlite to martensite.

Abstract: Oxide-dispersion strengthened (ODS) ferritic stainless steels have been considered as promising high-temperature materials such as interconnects for oxide-fuel cells and nuclear materials for Liquid Metal Fast Reactors or Super-Critical-Water-Cooled Reactors. In the present work, we have prepared Fe-14Cr-2Al-1Si-0.3Ta-1Y2O3 ferritic stainless steels which were dispersion-strengthened by nano-sized Y2O3 via mechanical alloying of elemental powder mixtures and subsequent hot consolidation. A comparison was made with MA 957 and DY-01 alloys. The mechanically alloying behaviour and consolidated mechanical properties of the Fe-14Cr-2Al-1Si- 0.3Ta-1Y2O3 ferritic steels were strongly influenced by processing parameters, especially milling atmosphere. The stability of yttrium oxides and oxidation resistance at high temperatures were examined. The preliminary result shows that the mechanically alloyed Fe-14Cr-2Al-1Si-0.3Ta- 1Y2O3 ferritic stainless steel exhibits interesting properties to be exploited as high temperature materials.