Additive manufacturing of stellite 6 superalloy by direct laser metal deposition - Part 1: Effects of laser power and focal plane position
Additive manufacturing of stellite 6 superalloy by direct laser metal deposition - Part 1: Effects of laser power and focal plane position
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DOI：
10.1016/j.optlastec.2020.106328
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发表时间：
2020-11-01
影响因子：
5
通讯作者：
Hasani, Arman
中科院分区：
文献类型：
--
作者：
Moradi, Mahmoud;Ashoori, Ali;Hasani, Arman
本文通过直接激光金属沉积法（DLMD）对司太立6钴基高温合金增材制造（AM）进行了实验研究。在本研究中，使用了同轴喷嘴头与最大功率为1 kW的连续光纤激光器耦合。当前研究的目的是研究 DLMD 增材制造的两种策略；第一个是改变粉末流内激光束的焦平面位置，即粉末集中平面上方 4 毫米和下方 4 毫米，第二个是研究激光功率（100-300 W）的变化。研究了 3D 打印墙壁样品的几何尺寸（高度和宽度）、显微硬度分布、晶粒尺寸和微观结构等特征。研究了增材制造墙壁在高度方面的稳定性。结果表明，将焦平面位置定位在基底上方，导致激光束和粉末流之间的相互作用面积更大，并导致AMed壁的高度更高。结果表明，当焦平面位置越接近粉流焦点时，获得的稳定性越好。通过将激光光斑点定位在粉末集中平面上方 2 mm，可实现更好的稳定性。增加激光功率会对高度和稳定性产生相反的影响：激光功率越大，AMed 墙的高度越高，观察到的稳定性越低。结果表明，100 W和150 W的激光功率具有最高的高度稳定性。样品晶粒尺寸的变化趋势表明AMed壁的开始和结束比样品中心更显着，显微硬度变化趋势与晶粒尺寸相反。此外，当激光功率增加时，平均晶粒尺寸也会增加。对于最高和最低激光功率，最大和最小平均晶粒尺寸分别为3.13μm和2.11μm。
This paper surveys the additive manufacturing (AM) of stellite 6 Cobalt-based superalloy by direct laser metal deposition method (DLMD) experimentally. In the present research, a coaxial nozzle head coupled with a continuous fiber laser with a maximum power of 1 kW was used. The purpose of the current research is investigating two strategies for DLMD additive manufacturing; the first one was changing the focal plane position of the laser beam inside the powder stream, 4 mm above and 4 mm below the powder concentration plane, and the second one was investigating the variation of the laser power (100-300 W). Some characteristics such as the geometrical dimensions (height and width), microhardness profile, grain size, and microstructure of the 3D printed wall samples were studied. The stability of the additively manufactured wall in terms of height was investigated. The results indicated that locating the focal plane position above the substrate, led to the more interaction area between the laser beam and powder stream and caused the higher height of the AMed wall. Results showed that when the focal plane position is near to the powder stream focus, the more stability will be obtained. By locating the laser spot point 2 mm above the powder concentration plane, better stability achieved. Increasing the laser power has a reverse effect on the height and stability: the more laser power, the higher height of the AMed wall, and the less stability observed. Results indicate that the laser power of 100 and 150 W has the highest height stability. The trend of changes in the grain size of the samples shows that the beginning and the end of the AMed wall are more significant than the sample's center and the trend of the microhardness variation is in a reverse regime of the grain size. Also, the average grain size will be increased when the laser power increased. The largest and the smallest average grain size are 3.13 mu m and 2.11 mu m for the highest and the lowest laser power, respectively.