爆炸-轧制TA1/Q345R复合板的组织与性能

Research on Microstructure and Properties of TA1/Q345R Clad Plates Prepared by Explosive Welding-Rolling Process

采用爆炸-轧制法制备了TA1/Q345R复合板,并通过拉剪试验对其结合性能进行了测试。借助光学显微镜观察了结合界面附近的显微组织,并利用扫描电镜(配X射线能谱仪)分析了拉剪试样钢侧的断口形貌。结果表明,与爆炸复合板相比,爆炸-轧制复合板的界面结合强度大幅降低,主要原因是结合界面形成了大量脆性中间相,为复合板的断裂失效提供了裂纹源。爆炸-轧制复合板结合界面为平直型界面,界面附近钢侧的微观组织特征有轻微的带状组织、铁素体粗晶区以及多种脆性中间相。剪切应力作用下,爆炸-轧制复合板主要沿轧制形成的原始表面分离,同时含有解理断裂和硬脆相破碎等特征。

TA1/Q345 R clad plates were prepared by explosive welding-rolling process and their bonding properties were tested by tension-shear test.The microstructures of interface between TA1 and Q345 R were observed by optical microscopy.Fracture morphology of tensile-shear samples at the steel side was analyzed by scanning electron microscope equipped with an energy-dispersive spectrometer(EDS).The results show that bonding strength of clad plates prepared by explosive welding-rolling process substantially reduce compared with that of clad plate prepared by explosive welding process.The main reason is that a large number of new brittle-phases form at the bonding interface between TA1 and Q345 R and become the crack source of the fracture failure.The interface of between TA1 and Q345 R prepared by explosive welding-rolling process is flat and the main microstructural characteristics near it at the steel side are as follows:slight banded structure,coarse grain region of ferrite and diversified brittle-phases.Under the action of shearing stress,the plates fracture along the original surfaces formed during the rolling process and cleavage fracture and breaking of brittle phases occur at the same time.