Microstructure and mechanical properties of TA15/TC11 graded structural material by wire arc additive manufacturing process

丝材电弧增材制造TA15/TC11梯度结构材料的显微组织和力学性能

A graded structural material(GSM)with a material transition from TA15 to TC11 was fabricated by wire arc additive manufacturing(WAAM)method.The grain morphology,chemical composition,microstructure and mechanical properties of the as-deposited GSM were all characterized to investigate their variations along the deposition direction.The results indicate that from TA15 to TC11,the grain size decreases and a transition from columnar grains to equiaxed grains occurs.The content of alloy element alters greatly within a short distance,and the width of the mutation zone is 800μm.Both TA15 and TC11 regions exhibit basketweave microstructure withα-phase andβ-phase.However,during the transition from TA15 to TC11,theα-lath becomes fine,which leads to an increase in microhardness.The tensile test shows that the bonding strength at the interface is higher than the longitudinal strength of TA15,and the lateral elongation at the interface is higher than that of TA15 and TC11.

利用丝材电弧增材制造的方法制备从TA15过渡为TC11的梯度结构材料,并对该梯度结构材料的晶粒形态、化学成分、显微组织和力学性能沿沉积方向的变化情况进行表征和研究。结果表明,从TA15到TC11,晶粒尺寸减小,并且发生从柱状晶到等轴晶的转变。合金元素的含量在短距离内变化很大,突变区的宽度为800μm。TA15区域和TC11区域均呈现出α+β双相网篮状组织。随着从TA15到TC11的过渡,α板条变细,这导致显微硬度的增加。拉伸试验表明,界面处的结合强度高于TA15部分的纵向强度,界面处的横向伸长率高于TA15部分和TC11部分的横向伸长率。