Influence of Rare Earths on Improve Impact Property of Structural Alloy Steel with Extra Low Sulfur and Oxygen  

作　　者：郭锋 林勤 

机构地区：[1]College of Materials Science and engineering, Inner Mongolia University of Technology [2]Physical Chemistry Department, University of Science and Technology Beijing

出　　处：《Journal of Rare Earths》2007年第S2期273-277,共5页稀土学报（英文版）

基　　金：Project supported bythe Ministry of Science and Technology of China (2002BA315A-5)

摘　　要：The influence of rare earth lanthanum and cerium on impact property of structural alloy steel with extra low sulfur and oxygen was studied by impact test and microanalysis. The results showed that rare earths increased impact power of the steel when their contents were about 0.005%. Proper addition of rare earths could purify grain boundaries and decrease amount of inclusions, and reduced the possibility of crack growth along grain boundaries and through inclusions. Therefore, such steel could absorb more crack growth energy while it was impacted. However, if the content of rare earths is excessive, the grain boundary would be weakened and brittle-hard phosphates and Fe-RE intermetallic would be formed, which worsened impact toughness of steel.The influence of rare earth lanthanum and cerium on impact property of structural alloy steel with extra low sulfur and oxygen was studied by impact test and microanalysis. The results showed that rare earths increased impact power of the steel when their contents were about 0.005%. Proper addition of rare earths could purify grain boundaries and decrease amount of inclusions, and reduced the possibility of crack growth along grain boundaries and through inclusions. Therefore, such steel could absorb more crack growth energy while it was impacted. However, if the content of rare earths is excessive, the grain boundary would be weakened and brittle-hard phosphates and Fe-RE intermetallic would be formed, which worsened impact toughness of steel.

关 键 词：LANTHANUM CERIUM extra low sulfur and oxygen structure alloy steel impact toughness mechanism 

分 类 号：TG142.15[一般工业技术—材料科学与工程]