Classifying shape of internal pores within AlSi10Mg alloy manufactured by laser powder bed fusion using 3D X-ray micro computed tomography: Influence of processing parameters and heat treatment
Classifying shape of internal pores within AlSi10Mg alloy manufactured by laser powder bed fusion using 3D X-ray micro computed tomography: Influence of processing parameters and heat treatment
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DOI：
10.1016/j.matchar.2020.110225
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发表时间：
2020-05-01
影响因子：
4.7
通讯作者：
Mulvihill, Daniel M.
中科院分区：
文献类型：
--
作者：
Hastie, James C.;Kartal, Mehmet E.;Mulvihill, Daniel M.
通过激光粉末床熔合（LPBF）制造的金属零件的内部孔隙率由包括激光功率、扫描速度、扫描间距和层厚度的工艺参数决定。为了充分了解工艺参数的影响，重要的是要将3D中的工艺缺陷（孔隙）形状分类为球形度以外的形状。在本文中，AlSi 10 Mg样品制造使用30个独特的LPBF参数组合，并使用高分辨率X射线显微计算机断层扫描（X μ CT）进行分析。单个孔隙的形状进行了分类和研究，使用的方法的基础上的三维孔隙描述符与简化的人工对象的相似性。通过热等静压（HIP），可以将高制造致密化构造内的孔隙率降低到几乎可以忽略不计，发现热等静压完全或部分封闭（压平）孔隙。随后的T6治疗导致毛孔重新打开，并类似于其原始形状。处理效果对孔径大小敏感。
Internal porosity of metallic parts manufactured by laser powder bed fusion (LPBF) is governed by processing parameters including laser power, scanning speed, scan spacing and layer thickness. To fully understand the influence of processing parameters it is important to categorise the shape of process defects (pores) in 3D beyond the degree of sphericity alone. In the present paper, AlSi10Mg samples were manufactured using 30 unique LPBF parameter combinations and analysed using high resolution X-ray micro computed tomography (X mu CT). The shapes of individual pores are classified and studied using an approach based on the similarity of 3D pore descriptors with simplified artificial objects. Porosity within high as-fabricated densification builds can be reduced to virtually negligible by hot isostatic pressing (HIPping), which was found to fully or partially close (flatten) pores. Subsequent T6 treatment causes pores to reopen and resemble their original shape. The effects of treatment are sensitive to pore size.