CAJ | 학술논문

研究了镍基合金825在550℃/25 M Pa、600℃/25 M Pa和650℃/25 M Pa超临界水（SCW ）中的应力腐蚀开裂敏感性，以及在超临界650℃/25 M Pa、次临界290℃/15.2 M Pa水中的均匀腐蚀性能。通过慢应变速率拉伸实验得到了相应的应力-应变曲线，结果表明，随温度的升高，825的机械强度和塑性逐渐下降；实验后试样的SEM图像表明，825在3种工况下的应力腐蚀开裂倾向大小关系为600℃＞550℃＞650℃。825在SCW条件下的腐蚀实验表明，其腐蚀增重大致符合幂函数生长规律；而其在次临界条件下的腐蚀增重变化却呈现出先减后增的特征。
연구료얼기합금825재550℃/25 M Pa、600℃/25 M Pa화650℃/25 M Pa초림계수（SCW ）중적응력부식개렬민감성，이급재초림계650℃/25 M Pa、차림계290℃/15.2 M Pa수중적균균부식성능。통과만응변속솔랍신실험득도료상응적응력-응변곡선，결과표명，수온도적승고，825적궤계강도화소성축점하강；실험후시양적SEM도상표명，825재3충공황하적응력부식개렬경향대소관계위600℃＞550℃＞650℃。825재SCW조건하적부식실험표명，기부식증중대치부합멱함수생장규률；이기재차림계조건하적부식증중변화각정현출선감후증적특정。
The susceptibility to stress corrosion cracking (SCC) of nickel based alloy 825 was studied in supercritical water (SCW) at 550 ℃/25 MPa ,600 ℃/25 MPa and 650 ℃/25 MPa respectively ,and their general corrosion behavior was researched in supercritical w ater at 650 ℃ /25 M Pa and in subcritical w ater at 290 ℃/15.2 M Pa respectively .The strain-stress curve obtained from slow strain rate tensile tests (SSRT ) shows that the strength and elongation of alloy 825 decrease with the increase of temper-ature .The ex-situ scanning electron microscopy shows that the SCC susceptibility of alloy 825 is 600 ℃ >550 ℃ >650 ℃ .T he general corrosion experiment in SCW show s that the weight gain is subject to power function growth rule ,while the one in subcriti-cal water indicates the weight loss and then weight gain .