离心铸造高速钢轧辊裂纹形成机理研究

通过分析离心铸造高速钢轧辊凝固过程和裂纹形成条件,发现离心铸造高速钢轧辊裂纹形成的主要原因是高速钢轧辊凝固层强度低,且与铸型产生间隙,不足以承受离心压力所致.裂纹源萌生后,在离心铸造系统长时间工作环境下,轧辊不能自由凝固收缩,促进裂纹的扩展.中间层凝固和轴向凝固的出现,不利于获得致密的轧辊组织,促进轧辊产生裂纹.

Study on Crack Forming of Centrifugal Cast High Speed Steel Roll

By analyzing the solidification process and the condition forming crack in the production of centrifugal cast high speed steel (HSS) roll, it was found that the main cause forming crack was the low strength of HSS roll solidification layer and clearance between solidification layer and mould existed, and HSS roll solidification layer could not endure large centrifugal pressure. In the common centrifugal casting condition, the free solidification constriction of HSS roll was difficult, that accelerated the crack source expanding. The appearance of mesosphere solidification and shaft direction solidification was unfevorable to obtain compact roll structures that accelerated the roll to produce crack.