304/Q245R爆炸复合板覆板侧结合界面的组织和硬度

Microstructure and nano-hardness of bond interfacial zone of 304/Q245R explosive welding composite plate

关键词:  爆炸焊接  奥氏体覆板  结合界面  纳米硬度  强化机理

Key words:  explosive welding  austenitefly plate  bond interfacezone  nano indenter  hardening mechanism

摘要:

采用扫描电镜、X射线衍射仪和纳米压痕仪等手段，分析了消应力退火后304/Q245R爆炸复合板不锈钢覆板侧结合界面的组织结构和硬度.白亮带区由动态再结晶所形成的相变马氏体和奥氏体纳米晶构成；纤维区由剧烈变形拉长奥氏体晶粒和其孪晶交叉处形成的马氏体构成；变形区由扭转变形奥氏体晶粒和其孪晶交叉处形成少量马氏体构成.白亮带、纤维区和变形区与原始奥氏体区未变形区相比的纳米硬度分别提高32%，13.5%和9.1%，白亮区的纳米晶强化以及纤维区较变形区较大的马氏体相变强化为其主要原因.

Abstract:

The bond interfacial structure of fly plate and its influence on the hardness of explosive welding 304/Q245R composite plate after stress relief annealing were investigated by means of scanning electron microscope, X-ray diffractometer and nano indentation etc. The white-layer zone was constituted by nano-sized austenitic and martensitic grains, which formed by dynamic recrystallized. The fiber zone was composed by tempestuously elongated strips austenitic grains and martensitic grains which located on twin intersections. The fiber zone was composed by tempestuously elongated strips austenitic grains and martensitic grains which located on twin intersections. The deformated zone was composed by tempestuously torsional austenitic grains and a small amount of martensite grains which located on twin intersections. The nano hardness of white-layer zone, fiber zone and deformated zone increased by 32%, 13.5% and 9.1% respectively compared with initial austenite zone of fly plate. The nanocrystalline strengthening of the white layer zone and compared with the deformation zone, the martensite phase transformation strengthening of the fiber zone which is larger were the main reasons.