摘要
选用Φ1.2mm的5A06铝焊丝为成形材料,研究TIG丝材-电弧增材制造工艺。以TIG焊机为电源(交流模式),以四轴联动数控机床为运动机构,研究单层和多层成形时预热温度和电流对成形形貌的影响,观察成形件微观组织,并测试其力学性能。建立了单层单道基板预热温度和电弧峰值电流工艺规范带判据,以保证良好成形。结果表明:成形件的高度从第一层的3.4mm急剧下降,直到第8层后高度稳定在1.7mm。层间组织为细小的树枝晶和等轴晶;层间结合处组织最粗大,为柱状树枝晶;顶部组织最细小,由细小的树枝晶转变为等轴晶。成形件的力学性能各向同性,抗拉强度为295MPa,伸长率为36%。
Wire and arc additive manufacturing（WAAM）was investigated by tungsten inert gas arc welding method（TIG）,in which Φ1.2mm filler wire of aluminum alloy 5A06（Al-6Mg-Mn-Si）was selected as deposition metal.The prototyping process was conducted by a TIG power source（working in AC mode）manipulated by a four-axis linkage CNC machine.Backplate preheating temperature and arc current on deposited morphologies of single layer and multi-layer were researched.The microstructure was observed and the sample tensile strength was tested.For single layer,a criterion that describes the correlation between backplate preheating temperature and arc peak current,of which both contribute to the smoothening of the deposited layer.The results show that the layer height drops sharply from the first layer of 3.4mm and keeps at 1.7mm after the 8th layer.Fine dendrite grain and equiaxed grain are found inside a layer and coarsest columnar dendrite structure at layer boundary zone;whereas the microstructure of top region of the deposited sample changes from fine dendrite grain to equiaxed grain that turns to be the finest structure.Mechanical property of the deposited sample is isotropic,in which the tensile strength is approximately 295 MPa with the elongation around36%.
出处
《材料工程》
EI
CAS
CSCD
北大核心
2017年第3期66-72,共7页
Journal of Materials Engineering
基金
国家自然科学基金资助项目(51475376)
西北工业大学凝固技术国家重点实验室自主研究课题资助项目(109-QP-2014)
