激光沉积修复ZL114A铝合金的组织及力学性能

发布时间：2018-05-19 05:32

本文选题：激光沉积修复 + ZLA铝合金　；参考：《稀有金属材料与工程》2017年06期

【摘要】：采用6 k W光纤激光器对预制槽损伤的ZL114A铸造铝合金进行激光沉积修复实验研究,分析了热处理前后激光修复区的组织形貌及分布规律,并对试样的显微硬度和室温拉伸性能进行了测试。结果表明,修复区与基材形成良好的冶金结合,沉积区底部为近似平行于熔合线法线外延生长的柱状树枝晶,一次枝晶间距约15.7μm,二次枝晶间距约5.2μm,共晶组织呈分叉棒状或块状连续分布于枝晶间隙,在沉积层顶层顶部出现α-Al柱状枝晶转变为等轴枝晶现象。热处理后修复区柱状枝晶的二次枝晶臂因高温原子扩散作用,连成一片,且共晶Si相粒状化明显,粒径约4.93μm,部分颗粒均匀分布于一次枝晶臂的两侧。热处理后修复区硬度较沉积态平均提高约1.6倍,且修复试样的室温拉伸力学性能优于铸造基材。
[Abstract]:A 6 K W fiber laser was used to study the laser deposition of ZL114A cast aluminum alloy damaged by the prefabricated slot. The microstructure and distribution of the laser repaired area before and after heat treatment were analyzed. The microhardness and tensile properties of the sample were tested. The results showed that the metallurgical bonding was formed between the repair area and the base material. The bottom of the sedimentary area is columnar dendrite, which is approximately parallel to the extension of the fusion line. The primary dendrite spacing is about 15.7 mu m, and the two dendrite spacing is about 5.2 mu m. The eutectic tissue is distributed in the intergranular space of the branch bar or lump, and there is an alpha -Al columnar dendrite in the top layer of the sedimentary layer to the equiaxed dendrite. After heat treatment, the repair zone column is made. The two dendrite arm of the dendrite is connected by high temperature atom diffusion, and the eutectic Si phase is granular, and the particle size is about 4.93 m. Some particles are evenly distributed on both sides of the first dendrite arm. The hardness of the repair area after heat treatment is about 1.6 times higher than that of the sedimentary state, and the tensile mechanical properties of the repaired specimens are better than the foundry substrate.
【作者单位】：沈阳航空航天大学航空制造工艺数字化国防重点学科实验室;
【基金】：国家自然科学基金(51505301,51305280,51375316) 辽宁省自然科学基金(2015020118)
【分类号】：TG146.21;TG665

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