Alloy20合金锻件焊接裂纹分析

Analysis of Welding Crack of Alloy20 Alloy Forging

为了分析某Alloy20合金锻件焊接后出现裂纹的原因,对锻件焊管取样并进行化学成分、力学性能、裂纹金相、晶粒度等试验检测。结果显示,该锻件试样的化学成分及拉伸性能均满足标准要求;晶粒度达到0级,锻件组织为严重粗晶组织,并且锻件晶界有碳化物析出相;锻件试样裂纹为沿晶裂纹。结果表明,该Alloy20合金锻件焊接后出现的裂纹为较低焊接应力下的低塑性焊接热裂纹。

In order to analyze the causes of cracks in an Alloy20 forgings after welding,the welded pipes of the forgings were sampled and tested for chemical composition,mechanical properties,crack metallography and grain size.The results show that the chemical composition and tensile properties of the forging sample meet the standard requirements.The grain size reaches 0 grade,the forging structure is severe coarse grain structure,and there are carbide precipitates in the grain boundary of the forging.The forging sample cracks are intergranular cracks.The results show that the cracks appeared after welding of the Alloy20 forging are low plastic welding thermal cracks under low welding stress.