大线能量工程结构钢热影响区模拟力学研究

Simulation Study on Heat Affected Zone of Steel for Large Wire Energy

利用热模拟仪、金相、扫描电镜等显微结构观察及力学性能表征手段模拟研究了一种大线能量用钢粗晶热影响区域的组织微观特征,结果表明:模拟试样具有优秀的综合力学性能,其微观组织主要由晶内针状铁素体与贝氏体组成,复合夹杂物由分布在颗粒内部的Ti2O3、Zr O2、Al2O3和位于表层的Mn S组成。这种复合夹杂能够促进形成针状铁素体,进而细化组织,而位于原奥氏体晶界上的夹杂物则能够促进形成多边形铁素体。

The microscopic characteristics of steel for large wire energy were studied by the thermal simulation instrument, the mechanical properties testing equipment and scanning electron microscope. The results show that the simulated specimen with excellent comprehensive mechanical properties was mainly consists of intra-granular acicular ferrite grain and bainite composition, composite inclusions by Ti2O3, ZrO2, Al2O3 distributed in the interior of the particles and MnS in the surface. The composite inclusions can promote the formation of acicular ferrite and microstructure refinement, while those in the micro-original austenite grain boundary can promote the formation of polygonal ferrite.