Hot isostatic pressing of IN718 components manufactured by selective laser melting
Hot isostatic pressing of IN718 components manufactured by selective laser melting
复制标题
DOI：
10.1016/j.addma.2016.11.006
复制
发表时间：
2017-01-01
影响因子：
11
通讯作者：
Hoyer, K-P
中科院分区：
文献类型：
--
作者：
Tillmann, W.;Schaak, C.;Hoyer, K-P
选择性激光熔化和其他增材制造（AM）技术最近引起了研究人员和加工行业的极大兴趣。设计的自由带来了全新的可能性，从而带来了全新的产品。在选择性激光熔化（SLM）工艺中，使用激光束逐层生产部件。SLM是一种基于粉末床的AM工艺，其特征在于所用粉末材料的完全熔化。采用SLM，可以直接从3D CAD数据生产复杂的三维零件和轻质结构。然而，尽管可持续土地管理是一项非常有前途的技术，但仍有挑战需要解决。在本研究中，仔细看看孔隙度。在循环载荷下，孔隙可作为应力集中器并导致过早裂纹萌生，这降低了材料的疲劳强度。热等静压（HIP）提供了降低孔隙率的可能性。热等静压结合了高压和高温，生产出具有上级性能的材料。采用显微X射线计算机断层扫描和扫描电子显微镜研究了热等静压工艺参数对IN718 SLM构件致密度和显微组织的影响。实验结果表明，热等静压可使大部分孔隙致密化。另一方面，一些孔隙不能被致密化。其原因在于SLM工艺中夹带的氩气。(C)2016爱思唯尔B.V.保留所有权利。
Selective laser melting and other additive manufacturing (AM) techniques have recently attracted substantial interest of both researchers and the processing industry. The freedom of design leads to completely new possibilities for constructions and, thus, to entirely new products. In the selective laser melting (SLM) process, the components are produced layer-wise using a laser beam. SLM is a powder bed based AM process and is characterized by the complete melting of the utilized powder material. Employing SLM, complex three-dimensional parts and light weight structures can be produced directly from 3D CAD data. However, although SLM is a very promising technology, there are still challenges to solve. In the present study, a close look is taken at the porosity. Under cyclic loading, pores can act as stress raisers and lead to premature crack initiations, which reduce the fatigue strength of the material. Hot isostatic pressing (HIP) offers the possibility to reduce the porosity. HIP combines high pressure and high temperature to produce materials with superior properties. The influence of the HIP process parameters on the density and microstructure of IN718 SLM components is investigated by means of micro X-ray computed tomography and scanning electron microscopy. The results of the experiments show that the majority of pores can be densified by means of HIP. On the other hand, some pores cannot be densified. The reason for this is seen in entrapped argon gas from the SLM process. (C) 2016 Elsevier B.V. All rights reserved.