铝板拉直机的固定机架裂纹分析  

Cracking Analysis of Fixed Pillar in Aluminum Plate Straightening Machine

作　　者：谭莹[1] 莫明珍[1] 周崎[1] 曹标[1] 

机构地区：[1]广东出入境检验检疫局检验检疫技术中心,广东广州510623

出　　处：《铸造》2013年第9期920-921,924,共3页Foundry

摘　　要：铝板拉直机在试机时,其固定机架在外载荷未达设计值开裂。采用宏观、微观断口分析及金相检查,结果显示,固定机架开裂由铸造缺陷引起。该缺陷位于铸件的受力部位,同时也是铸件的热节及冒口部位。由于冒口尺寸设计不合理等,导致补缩不良,加之放置在冒口附近的内冷铁表面清理不当,形成了内冷铁未完全熔合及缩孔等组织不连续缺陷,导致局部应力集中,使其实际承载能力下降,这是固定机架开裂的主要原因。The fixed pillar of aluminum plate straightening machine cracked under the condition which its external load did not reach the design value.The failure of fixed pillar was analyzed by ways of macro-fractography,micro-fractography analysis and metallographic analysis.The result shows that the cracking of fixed pillar was caused by the casting defects.The defects were located at the stress zone of the fixed pillar where the hot spot and the riser were.The unreasonable design of the riser dimension resulted in feeding badness.The surface of the internal denseners near the riser was not cleaned,which formed incompletely melted denseners and shrinkage.So the stress concentration was formed in the discontinuous zone,which resulted in declining of the actual bearing capacity and was the main reason for the crack of the fixed pillar.

关 键 词：固定机架 铸造缺陷 开裂 

分 类 号：TG305[金属学及工艺—金属压力加工]