Mg-Ti复合脱氧对低碳微合金钢组织性能的影响

Effect of Mg-Ti Multiplicity Deoxidizing on the Microstructure and Properties of Low Carbon Microallyed Steel

通过焊接热模拟和冲击韧性试验,研究了Mg-Ti脱氧和Al脱氧在大线能量焊接热循环条件下对低碳微合金钢粗晶区组织性能的影响。结果表明,Mg-Ti脱氧钢粗晶区的组织主要是针状铁素体(AF)和少量的多边形铁素体,Al脱氧钢粗晶区的组织主要是低碳贝氏体+大量的块状铁素体。对Mg-Ti脱氧钢和Al脱氧钢在不同焊接热循环下的冲击韧性进行研究,结果表明随着焊接热输入量的增大,两种脱氧钢的冲击韧性都有所下降,但是从总体上来说Mg-Ti脱氧钢粗晶区的冲击韧性远远高出Al脱氧钢粗晶区的冲击韧性。

Effect of Mg-Ti multiplicity deoxidizing on the microstructure of low carbon microallyed steel was investigated by weld thermal simulation and the charpy test.The results showed that the structure of heat-affected-zone was acieular ferrite and a little polygonal ferrite in Mg-Ti deoxidized steel, and in Al deoxidized steel the structure of heat-affected-zone was plenty of polygonal ferrite and pearlite. And the impact of Mg-Ti and Al deoxidizing steel at different welding thermal cycle was also investigated. It showed that the impactive toughness declines as the heat imput was higher, and the impactive toughness of Mg-Ti deoxidizing steel was higher than that of Al deoxidizing steel.