摘要
在热分析仪上采用增重法对稀土含量不同的低合金钢进行抗高温氧化实验,利用扫描电镜(SEM)进行氧化形貌观察。结果表明,温度为1050℃和1150℃时,恒温氧化动力学均符合抛物线规律,氧化膜具有保护性,稀土含量为0.0134%和0.0095%的低合金钢氧化反应激活能比不含稀土的低合金钢分别提高了71%和57%。在1050℃时稀土含量为0.0134%和0.0095%的低合金钢氧化速率常数比不含稀土的低合金钢降低了30%和20%,在1150℃时降低了7%和3%。稀土的添加提高了低合金钢的反应激活能,降低了氧化速率常数,提高低合金钢的抗高温氧化性能,并且稀土含量越高,抗高温氧化性能越强;在1250℃时生成的氧化膜保护性差,含稀土的钢氧化速率快,不利于提高低合金钢的抗氧化性。稀土的加入细化了氧化膜的晶粒,增强了氧化膜与基体的粘附性,使氧化膜不易脱落。
By the method of weight gain, high temperature oxidation experiment for low alloy steel with different content of rare earth was conducted and oxidation morphology was observed by scanning electron microscopy （SEM）. The results show that, at 1050 ℃ and 1150℃, the temperature oxidation kinetics are in line with the parabolic law, protective oxide films are formed, and oxidation reation activation energies of low alloy stees with rare earth content of 0. 0134% and 0.0095% are 90% and 53% higher respectively than that without rare earth. Oxidation rate constants of low alloy steels with rare earth content of 0.0134% and 0. 0095% are 30% and 20% lower at 1050℃ ,7% and 3% lower at 1150℃ than that without rare earth. Adding rare earth ro low alloy steel can improve its reaction activation energy, reduce its oxidation rate constant and increase its high temperature oxidation resistance. The higher the content of rare earth, the higher the high temperature oxidation resistance. Oxide film formed at 1250℃ is lack of effective protective ,which makes rare earth steel be oxidized fast. Thus increasing temperature is not conductive to anti - oxidation improvement of the alloy steel. Addition of rare earth refined the grains of oxide films, enhanced the adhesivity of oxide film with substrate and made the oside films be not easy to fall off.
出处
《稀土》
EI
CAS
CSCD
北大核心
2016年第6期52-57,共6页
Chinese Rare Earths
基金
国家自然科学基金项目(51261018)
关键词
稀土
氧化动力学
氧化膜
抗氧化性
rare earths
oxidation kinetics
oxidation scale
oxidation resistance
