2A12T4铝合金棒材挤压开裂的原因及其预防措施  

Analysis of the causes and preventive measures against extrusion cracking in 2A12 aluminum alloy rods

作　　者：白晓霞[1] 张荣旺 李国栋 丛福官[1] 张辉玲[1] 刘炎清 BAI Xiaoxia;ZHANG Rongwang;LI Guodong;CONG Fuguan;ZHANG Huiling;LIU Yanqing(Northeast Light alloy Co.,Ltd.,Harbin 150060,China;CASIC Material Supply and Marketing Station,Beijing 100830,China)

机构地区：[1]东北轻合金有限责任公司,哈尔滨150060 [2]中国航天科工集团物资供销总站,北京100830

出　　处：《轻合金加工技术》2025年第1期41-45,共5页Light Alloy Fabrication Technology

基　　金：广西科技计划项目(桂科AB23026059,桂科AB23026114)。

摘　　要：观察了2A12T4铝合金挤压开裂棒材的头端和尾端的低倍组织,并借助金相显微镜和扫描电子显微镜对其显微组织和微区成分进行观察和分析,从而确定了挤压棒材开裂的主要原因。结果表明,挤压棒材开裂是由于铸锭中存在中心热裂纹,在挤压过程中造成棒材头端开裂。棒材尾端出现具有铸锭中心裂纹特征的细纹,裂纹中填充低熔点共晶,该共晶与正常组织中的低熔点相基本一致。By conducting macrostructural observations on both the head and tail ends of the extruded 2A12T4 aluminum alloy rods with cracks,coupled with metallographic and scanning electron microscopy analysis to examine the microstructure and micro-regional composition,the primary causes of extrusion cracking have been pinpointed.The analysis unveiled that the cracking originated from low-melting eutectic phases filling the central hot cracks within the ingots.Consequently,during the extrusion process,cracks emerged at the head end of the rods.Meanwhile,fine cracks resembling ingot center cracks were observed at the tail end.The low-melting eutectic phases filling these cracks were largely similar to those found in the normal microstructure.

关 键 词：2A12T4铝合金 铸造热裂纹 中心裂纹 低熔点共晶 挤压开裂 

分 类 号：TG146.21[一般工业技术—材料科学与工程] TG379[金属学及工艺—金属材料]