Effect of Aluminum and Titanium Treatment on Non-metallic Inclusions and Microstructures of CGHAZ in HSLA Steel
Effect of Al and Ti treatment on non-metallic inclusions and microstructures of coarse-grain HAZ in HSLA steel was investigated in this paper based on experiments and thermodynamic calculations.The results showed that the inclusions in Al treated steel were mainly aluminum oxides and titanium nitrides which could not promote the formation of acicular ferrite microstructures. Microstructure of coarse-grain HAZ in Al treated steels consists of heavy grain boundary ferrite and ferrite side plate. The inclusions in Ti treated steel were Al，Ti，Mg，Ca composite oxides with size in the range of 0.5-3μm and titanium nitrides with size less than 0.3μm. Ti composite oxide could promote the formation of acicular ferrite and microstructures of coarse-grain HAZ in Ti treated steel consists of grain boundary ferrite, small amounts of ferrite side plate and large amounts of intragranular acicular ferrite. The size of grain boundaries ferrite was increased and the amount of ferrite side plate was decreased with the increase of soaking time at the peak temperature. The amount of grain boundary ferrite and the size of acicular ferrite were also increased with the increase of cooling rate during ferrite phase formation.
Ti treatment A1 treatment coarse grain HAZ grain boundary ferrite acicular ferrite
CHAI Feng YANG Cai-fu SU Hang Zhang Yong-quan
China Iron and Steel Research Institute, Beijing 100081, China
国际会议
The 6th International Conference on High Strength Low Alloy Steels(第六届高强度低合金钢国际会议HSLA Steels2011)
北京
英文
583-587
2011-05-31（万方平台首次上网日期，不代表论文的发表时间）