研究了在zr_4合金中添加2wt%Cu的合金显微组织及其在500℃和10.3MPa过热蒸汽中的耐腐蚀性能。结果表明,该合金经过热轧、冷轧以及经2h、580℃真空退火处理后,得到以α-Zr为基体的显微组织,合金中主要存在四方结构的Zr,Cu和密排六方结构的zr(Fe,cr,Cu)2第二相,Zr2Cu相有长度1~4μm、厚度约1μm的片状和直径300~500nm的球形两种形态,并且都会富集一定量的Fe元素。在10.3MPa、500qC过热水蒸汽中,添加2wt%cu的zr-4合金不发生疖状腐蚀,表明cu是改善锆合金耐疖状腐蚀性能的有益元素。
The effects of the 2 wt% copper addition on microstructures and the corrosion behaviors of Zirealoy-4 alloys in the 500 °C superheated steam of 10.3 MPa were investigated. The main phase was α-Zr after hot rolled, cold rolled and subsequent vacuum annealing treatment (580 ~C for 2 h). Furthermore, tetragonal-Zr2Cu and hexagonal-Zr ( Fe, Cr, Cn) 2 precipitates were observed by TEM. Enrichment of Fe element was found in lamellar (about 1 -4 μm and 1 μm in length and thickness, respectively) and spherical (300 -500 nm in diameter) Zr2Cu phases. Nodular corrosion was not observed in Zr-4-2Cu after 500 h corrosion in 500 ° C superheated steam of 10.3 MPa, indicating that Cu was beneficial to improving the nodular corrosion resistance of Zircaloy alloy in the environment stated above.