退火工藝對Zr-Sn-Nb-Fe-Si合金耐腐蝕性能的影響退火工藝對Zr-Sn-Nb-Fe-Si合金耐腐蝕性能的影響Effect of annealing treatments on corrosion resistance of Zr-Sn-Nb-Fe-Si alloy SZA-6(Zr-(0.35~0.65)Sn-(0.35~0.65)Nb-(0.15~0.45)Fe-(0.01~0.02)Si)合金經(jīng)β相區(qū)水淬后經(jīng)500和580 ℃保溫5~50 h，通過靜態(tài)高壓釜腐蝕實(shí)驗(yàn)研究樣品在400 ℃、10.3 MPa過熱蒸汽和360 ℃、18.6 MPa、0.01 mol/L LiOH水溶液中的腐蝕行為。并利用SEM、TEM和EDS研究合金的顯微組織，包括第二相的尺寸、分布與種類。結(jié)果表明：經(jīng)500 ℃退火處理的樣品發(fā)生部分再結(jié)晶，經(jīng)580 ℃退火處理的樣品發(fā)生完全再結(jié)晶，退火時(shí)間對第二相尺寸的影響也不明顯，退火時(shí)間對第二相尺寸的影響不明顯；合金中的第二相主要是密排六方的Zr(Nb,Fe,Cr)2、四方的Zr5Si4以及正交的Zr3Fe；SZA-6合金在400 ℃、10.3 MPa過熱蒸汽與360 ℃、18.6 MPa、0.01 mol/L LiOH水溶液中的耐腐蝕性能均隨著退火溫度的升高而變差，退火時(shí)間對SZA-6合金的耐腐蝕性能影響不大。 Varies annealing temperature and annealing time (500~580 ℃, 5~50 h) were conducted to SZA-6 (Zr-(0.35-0.65)Sn-(0.35-0.65)Nb-(0.15-0.45)Fe-(0.01-0.02)Si) alloy, the effects of annealing treatments on the corrosion resistance of zirconium alloy were investigated. The annealing samples were corroded in lithiated water with 0.01 mol/L LiOH at (360 ℃, 18.6 MPa), as well as superheated steam at (400 ℃, 10.3 MPa). The microstructures of the samples were examined by SEM, TEM and EDS. The results show that samples annealed at 500 ℃ are in a partial recrystallization state and samples annealed at 580 ℃ are in a complete recrystallization state. Annealing time shows no obvious effect on the size of second phase particles(SPPs) in both samples. Hexagonal close packed Zr(Nb,Fe,Cr)2 SPPs, tetragonal Zr5Si4 and orthogonal Zr3Fe SPPs are observed in the matrix of the alloy. The corrosion resistance of SZA-6 alloy decreases with the increase of annealing temperature and is insensitive to the annealing time in the both water chemistries. Annealing time shows no obvious effect on the corrosion resistance of SZA-6 alloy.
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