丝材电弧增材制造技术制备316L不锈钢的力学性能  

Mechanical properties of 316L stainless steel fabricated by wire and arc additive manufacturing

作　　者：赵阳[1,2] 范若兰 刘玉锋 王震 ZHAO Yang;FAN Ruolan;LIU Yufeng;WANG Zhen(Space Structures Research Center,Zhejiang University,Hangzhou 310058,China;School of Civil Engineering,Shaoxing University,Shaoxing 312000,China;School of Engineering,Zhejiang University City College,Hangzhou 310015,China)

机构地区：[1]浙江大学空间结构研究中心,浙江杭州310058 [2]绍兴文理学院土木工程学院,浙江绍兴312000 [3]浙大城市学院工程学院,浙江杭州310015

出　　处：《建筑结构学报》2023年第8期207-216,共10页Journal of Building Structures

基　　金：国家自然科学基金项目(52078452);浙江省基础公益研究计划项目(LGG22E080005)。

摘　　要：丝材电弧增材制造(WAAM)技术具有沉积效率高、制造周期短、成本低以及尺寸限制小等优点,适用于结构工程领域大型金属构件的制造。针对316L奥氏体不锈钢材料,采用冷金属过渡电弧增材制造工艺(CMT-WAAM)制作了3种打印方向、2种打印厚度和3种取样方向的12组共36个试样。通过拉伸试验和统计分析,研究了材料的应力-应变曲线、主要力学性能指标及各向异性,并与已有文献的试验结果及相关标准中的数据进行了对比分析。进而通过扫描试验和金相分析,分析了材料断口形貌特征、金相显微组织及生成机理。结果表明:不同打印方向的沉积板沿纵向、横向和对角线等3个方向的力学性能有所差异,水平长边和竖直长边打印的沉积板均表现出显著的各向异性,而竖直短边打印的沉积板各向异性并不明显;随着打印厚度的增大,竖直短边打印的沉积板的各向异性趋于明显,但其力学性能基本都满足规范相关要求;断口表面存在大量均匀分布的等轴韧窝,断裂方式为韧性断裂;当产生位错滑移时,沉积板不同方向的晶界阻碍程度差异会引起其力学性能的各向异性。Wire and arc additive manufacturing(WAAM)technology has the advantages of high deposition efficiency,short period of manufacturing,low cost,and less size limitation,and is suitable for manufacturing large metal components in the field of structural engineering.For the material of 316L austenitic stainless steel based on cold metal transfer wire and arc additive manufacturing(CMT-WAAM)process,12 groups of 36 specimens with three printing directions,two printing thicknesses,and three sampling directions were prepared.Through tensile tests and statistical analysis,the stress-strain curves,main mechanical tensile properties,and anisotropy effects of the material were studied.The test results were compared with test results from existing literature and data from relative standards.By scanning electron microscope test and metallographic analysis,the fracture morphology,metallographic microstructure,and formation mechanism of the material were discussed.The results show that the mechanical properties of the deposited plates made in different printing directions are different along the longitudinal,transverse,and diagonal directions.The deposited plates printed on the horizontal long side and the vertical long side both show large anisotropy,but the anisotropy of the deposited plate printed on the vertical short side is not obvious.As the thickness of the deposited plate printed on the vertical short side increases,the anisotropy will become obvious,but the mechanical properties basically satisfy the existing code requirement for 316L stainless steel.The fracture type is ductile fracture due to the many uniform equiaxed dimples on the fracture surface.When the dislocation slip occurs,the degree of grain boundary obstruction is different in different directions,leading to the anisotropy of mechanical properties.

关 键 词：316L不锈钢 电弧增材制造 拉伸试验 力学性能 显微组织 

分 类 号：TU391[建筑科学—结构工程] TG142.1[一般工业技术—材料科学与工程]