1 Experimental In a laboratory,under an argon atmosphere 16Mn steel with low sulphur melted with pure Fe,C,Mn and Si in MgO crucible was carried out at 1653+5C in a molybdenum wire furnace.After melting the rare earth element Ce or La was added in the melten.Then we took some specimens for analysis of compo- sition.The 5kg 16Mn steel ingots were melted in a induction furnace and added Ce or La at 1580C under an argon atmosphere. Standard impact specimens were made by a ingot which was worked by turning,forging,rolling,planing,milling,and grinding.The impact values were measured at -60~+60C.Metallographic specimens were taken from top of every ingot to study the rare earth inclusions.They were observed with JAX- 50A scanning electron microscope (SEM)and Cambridge Instrument Quantimet 900 (CIQ-900).Specimens for measurement of alloying amount were made as a cylinder shape from the ingot which had been worked by stripping skin, turning and grinding.Then they were electrolysed to study alloying amount of the rare earth element.Polarization specimens were made as a regular geometric crnament.After polishing they were mounted in epoxy resin as a electrode.The anodic and cathodic polarization curves of the 16Mn steel with rare earth addition were tested with CMS-351.After that the ratio of corrosion and electro-che- mical properties have been calculated. 2 Result and Discussion 2.1 Deoxidation and Desulfuration of Rare Earth Element in the 16Mn Steel Rare earth elements have a great affinity to oxygen and sulphur.The expe- rimental results are given in Table 1. Table 1 Results of deoxidation and desulfuration from 16Mn steel with Ce Ce ppm 0.0 50.0 60.0 65.0 0 ppm 20.0 12.0 10.0 17.0 s ppm 25.0 22.0 21.0 21.0 From the Table 1 it has found that deoxidation has a minimun in the range of 50~60 ppm amount of Ce.A reaction of deoxidation with rare earth ele- ments is x〔RE)+y〔O)=RExO, 591」 压 ， ， ， 士 “ · “ ， ， ， ， ， 一 爪 一 一 “ · · 丁 一 · 功 ， · · 。 一 · 五 。 一 。 一 主 五 。 卜 卜 气 。 。 。 。 。 。 。 。 。 。 。 。 川 。 劣 〔 〕 〔 〕