工程机械用HG50和CF60钢的动态断裂韧性

INVESTIGATION ON THE DYNAMIC FRACTURE TOUGHNESS PROPERTIES OF HG50 AND CF60 STEELS USED FOR ENGINEERING MACHINERY

研究了两种低合金高强度工程机械用钢——ＨＧ５０和ＣＦ６０的母材和焊接接头（包括焊缝和焊接热影响区）在三种压头位移速率下的断裂韧性随着温度的变化行为，分析了加载速率和焊接工艺对于其断裂韧性的影响。结果表明：ＨＧ５０和ＣＦ６０钢的断裂韧性尽管对于加载速率很敏感，仍然具有较好的动态断裂韧性，适于用做承受冲击的工程机械的受力构件；焊接过程可造成韧—脆转变温度的升高，加大了韧—脆转变曲线过渡区的温度范围，并使得过渡区内的断裂韧性数据具有较大的发散性。

The dynamic fracture properties of two HSLA steels HG50 and CF60 used for engineering machinery and their weld joints were studiedTheir fracture toughness values versus temperature were measured respectively at three different crosshead ratesThe effect of microstructure and loading rate on fracture tougness were analyzedThe results show that HG50 and CF60 have good dynamic fracture toughness although which is sensitive to loading ratesAs a result of the welding process,the ductiletobrittle transition temperature and its range is increased markedly,and the experimental toughness data were dispersed within the transition zone 