【摘要】 用放射性同位素¹⁴¹铈检测了稀土夹杂在所选无水电解液及电解制度下之稳定性.实验证明硫化铈及氧化铈夹杂的破坏是微量的.测定了不同稀土含量的25MnTiB等五种钢中的合金化稀土量;原始O、S含量高,稀土含量低的钢中几乎无固溶稀土;随着稀土含量增加,合金化稀土量也不断增加.由于钢中稀土夹杂偏聚较大,实验结果表明,前人用稀土含量与夹杂中稀土量之差值确定钢中合金化稀土量的方法是不可靠的.微观自射线照相表明,25MnTiB中的稀土夹杂多偏聚于珠光体中,FeCrAl中的稀土在晶粒中呈条状分布,用自射线照相方法观察不到晶界处有Ce的富集.更多还原

【Abstract】 The stee samples containing cerium sulfide and cerium oxide traced by ~141Ce were electrolyzed to detect the stability of cerium sulfide and cerium oxide under the chosen conditions of electrolysis. The results of our experiments show that the decomposed amount of cerium sulfide and cerium oxide during electrolysis is extremely small, the former≤0.4%, the latter≤0.027%. The measurements of the cerium content in the 5 kinds of steel show: if the original content of S and O in steel before the addition of Ce is high, there is almost no dissolved cerium in the low Ce content steels. The alloying amount of Ce increases with the increase in Ce content in steels, Experimental results show that the method used by former researchers for determining the alloying amount of the rare earths by the difference between the total rare earth amount in the sample and the rare earth amount in the inclusions is unreliable owing to the segregation of rare earth inclusions in the steel.Microautoradiographs show that the inclusions containig cerium are more concentrated in pearlite of the as-cast 25MnTiB steel Ce is distributed in a strip shape within the grains of as-cast Fe-Cr-Al alloy. The concentration of Ce in the grain boundaries was not observed by the autoradiography.更多还原