以Mn、N代Ni奥氏体耐热钢的高温氧化

Oxidation resistant property of austenite heat-resistant steel replacing Ni by Mn and N

锅炉燃烧喷嘴(简称喷嘴)是发电厂锅炉燃烧设备的重要部件,用于把煤粉输送入锅炉的燃烧室内.它与锅炉连接的一端温度高达1 100℃,同时受到煤粉的冲刷磨损.因此,要求喷嘴在高温下具有良好的抗变形、抗氧化性和耐磨性.在25-20耐热钢成分的基础上,添加Mn、N,并减少Ni含量,以求达到降低锅炉燃烧器喷嘴材料成本的目的,由此研制出了几种耐热钢.将25-20钢与之在900、1 0001、150℃时的氧化做了对比试验,并通过高温氧化增重计算及氧化膜的X射线衍射分析,对新材料在高温条件下的氧化机理进行了研究和讨论.提出了在不同温度下可能替代25-20钢的钢种及依据.

The temperature at the end of burning spray nozzle, which is connected with boiler, is about 1 100℃, and the abrasion of the nozzle often occurs due to scouring effect of the high temperature coal powder. Hence, it requires that the nozzle have good deformation, oxidation and wear resistances at high temperature. In order to lowering the material cost of boiler nozzle, several heat-reslstant steels had been developed through adding Mn and N elements as well as decreasing the content of Ni on the basis of 25-20 hest-resistant steels. The comparative oxidation tests had been done for 25-20 steels and new developed materials at 900℃, 1 000℃ and 1 150℃. Through both calculation of the oxidation weight-gain and X-ray diffraction analysis on the oxide film, the oxidation mechanism of the new materials at high temperatures had been discussed. Furthermore, the new steel type with the possibility of replacing 25-20 steels and corresponding foundation had been suggested.