20Mn_2WNbB贝氏体钢焊接热影响区的显微组织和力学性能

MICROSTRUCTURE AND MECHANICAL PROPERTY OF HEAT AFFECTED ZONE OF WELD IN 20Mn_2WNbB BAINITE STEEL

用热模拟法研究了一种低碳低合金20Mn2WNbB热轧贝氏体钢焊技后的力学性能，得出其热影响区的变化规律与低碳铁素体加珠光体钢不同，显微组织分析证实，这是钢在冷却时发生了复杂的贝氏体、马氏体相变引起的．结果表明，这种钢焊后采用较快的冷却速度，有利于提高钢的强度及韧性。

Mechanical properties of 20Mn2WNbB hot-rolled bainite steel after weld by heat simulation is investigated in this paper. The differnt law of change in heat affected aone between this steel and the steel including low carbon ferrite and pearlite is caused by complicated transformations of bainite and martensite .The experimental result indicates that rapid cooling speed is veneficial to this steel to improve strength and toughness after weld.