摘要
研究了Fe－Mo－B－CU－C与Fe－Mo－Ni－Cu－C系粉末烧结钢中合金含量、碳加入方式、热处理等温温度对下贝氏体形成的影响，同时对形成的下贝氏体组织形貌进行了比较分析。结果表明：在Fe－Mo—B－Cu—C系中，当B含量在2％，等温热处理温度为350℃时，有较大量针状下贝氏体出现；在Fe-Mo-Ni－Cu－C系中，当碳以石墨粉形式加入时，含镍4％的烧结钢在等温热处理温度200℃及280℃下均获得典型下贝氏体组织；而以镍包石墨方式加入的合金系中，3％、4％的Ni（石墨）试样在等温热处理温度280℃下获得典型下贝氏体组织；以石墨粉形式加入和以镍包石墨形式加入形成的贝氏体显微形貌存在较大差异，前者贝氏体的分布均匀，体积分数较大。
This paper studies the formation and morphology of bainite structure of Fe- Mo-B-Cu-C and Fe-Mo- Ni -Cu-C sintered steel. The effect factors in forming bainite have been investigated, including alloy elements content, the adding ways of carbon and the heat treatment temperature. For Fe-Mo-B-Cu-C system,lower bainite can be obtained by heat treatment at temperature of 350℃ with 2% B, while for Fe-Mo-Ni-Cu-C system, the two ways of adding carbon (graphite powder and nickel-coat-graphite) can form acicular lower bainite with 4% Ni, heated treatment at temperature of 200℃ and 280℃ for adding graphite powder system, or heated treated at temperature of 280℃ for adding nickel-coat-graphite system. It is found that a large amount of bainite exist in the vicinity of solid-gas interfaces (such as pores surface), resulting from the inhomogeneity of carbon by losing carbon out off the interfaces. It is also observed that when carhon is added in form of nickel-coat-graphite, the acicular lower bainite tends to be more in amount, more homogeneous in distribution than those of graphite powder additions.
出处
《粉末冶金技术》
CAS
CSCD
北大核心
1999年第3期176-181,共6页
Powder Metallurgy Technology
关键词
粉末烧结钢
下贝氏体
等温热处理温度
powder sintered steel
lower bainite
heat treatment temperature
