摘要
利用彩色金相法研究了TMCP(Thermal-Mechanical Control Process)工艺生产的超高强度船体海洋工程钢中马氏体/奥氏体(M/A)在等温过程、连续冷却过程和回火时的演变特点。结果表明M/A的形态尺寸与分布主要取决于组织转变的温度,加长转变的时间长只对0.5μm以下微粒状M/A略有影响。冷却速度低于2℃/s时会形成尺寸在2μm以上较大的M/A,对钢的韧性有损害。另外,回火过程中尤其是600℃以上回火时,M/A的总量明显减少,M/A球团化趋势明显,M/A个体尺寸有明显增大,对钢的韧性起到破坏作用。
The evolution of martensite/austenite（M/A） microstructure formed during isothermal treatment,continuous cooling and tempering processes in a super high strength TMCP steel for ship hull and offshore structure was investigated by tint etching method.It is shown that the morphology,size and distribution of M/A mainly depends on transformation temperature,and the time of transformation slightly affects the particle M/A with the size less than 0.5 μm.Mass M/A bigger than 2 μm is observed in the steel with the cooling rate lower than 2 ℃/s,which deteriorates toughness of the steel.During tempering especially at the temperature higher than 600 ℃,the amount of M/A decreases drastically,and the morphology of M/A tends to be sphericized and it＇s size increases obviously,leading to the decrease of toughness.
出处
《材料热处理学报》
EI
CAS
CSCD
北大核心
2010年第2期51-55,共5页
Transactions of Materials and Heat Treatment
基金
国家"863"科研计划项目(2006.AA032507)
关键词
马氏体/奥氏体
组织
冲击韧性
回火
TMCP
船体钢
martensite/austenite
microstructure
impact toughness
tempering
TMCP
ship hull steel
