Investigating the microstructure of an additively manufactured FeCo alloy: an electron microscopy study

被引:12
作者
Pramanik, Sudipta [1 ]
Tasche, Lennart [1 ]
Hoyer, Kay-Peter [1 ]
Schaper, Mirko [1 ]
机构
[1] Paderborn Univ, Chair Mat Sci, Mersinweg 7, D-33100 Paderborn, Germany
关键词
Laser powder bed fusion; FeCo alloy; Microstructure; X-ray microtomography; High angle annular dark-field scanning trans-mission electron microscopy; High-resolution transmission electron microscopy; Energy-filtered transmission electron microscopy; ENERGY DENSITY; LASER; STEEL; PART; FLOW;
D O I
10.1016/j.addma.2021.102087
中图分类号
T [工业技术];
学科分类号
08 ;
摘要
The objective of the present investigation is to correlate mechanical properties with microstructure for FeCo alloy using electron microscopy. A short parameter adaption is conducted to determine the optimum laser powder bed fusion parameters, which lead to the highest sample density. Subsequently, FeCo alloy samples are produced to address the evolving microstructure and mechanical properties. A high build rate is also attained along with the high density. X-ray micro-tomography of the samples revealed a remaining porosity of 0.02%. Electropolishing and subsequent microstructural examinations are undertaken by electron backscatter diffraction employing scanning electron microscopy. Elongated columnar grains are observed on the side of the samples, which is characteristic of selective laser melting. Based on transmission electron microscopy, the composition of Fe and Co at the submicron scale is homogeneous. The dislocation density near the grain boundaries measured by transmission electron microscopy is approximate to 2.2 x 10(13) m(-2). Unresolved lattice fringes due to dislocation strain fields are observed in high-resolution transmission electron microscopy images. Different tensile properties are obtained with loading parallel as well as perpendicular to the build direction. This is due to different Schmid factors of the grains during loading parallel and perpendicular to the build direction. A mixture of cleavage and dimple fracture is noticed upon loading parallel to the build direction. Whereas loading perpendicular to the build direction shows only cleavage fracture.
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页数:13
相关论文
共 34 条
[11]   Additive manufacturing of metallic components by selective electron beam melting - a review [J].
Koerner, C. .
INTERNATIONAL MATERIALS REVIEWS, 2016, 61 (05) :361-377
[12]   Controlling the extent of atomic ordering in intermetallic alloys through additive manufacturing [J].
Kustas, Andrew B. ;
Fancher, Chris M. ;
Whetten, Shaun R. ;
Dagel, Daryl J. ;
Michael, Joseph R. ;
Susan, Donald F. .
ADDITIVE MANUFACTURING, 2019, 28 :772-780
[13]   Characterization of the Fe-Co-1.5V soft ferromagnetic alloy processed by Laser Engineered Net Shaping (LENS) [J].
Kustas, Andrew B. ;
Susan, Donald F. ;
Johnson, Kyle L. ;
Whetten, Shaun R. ;
Rodriguez, Mark A. ;
Dagel, Daryl J. ;
Michael, Joseph R. ;
Keicher, David M. ;
Argibay, Nicolas .
ADDITIVE MANUFACTURING, 2018, 21 :41-52
[14]   RELATIONSHIP BETWEEN FLOW STRESS + ATOMIC ORDER IN FECO ALLOY [J].
MARCINKOWSKI, MJ ;
CHESSIN, H .
PHILOSOPHICAL MAGAZINE, 1964, 10 (107) :837-&
[15]   Tuning the phase stability and magnetic properties of laser additively processed Fe-30at% Ni soft magnetic alloys [J].
Mikler, C. V. ;
Chaudhary, V. ;
Soni, V. ;
Gwalani, B. ;
Ramanujan, R. V. ;
Banerjee, R. .
MATERIALS LETTERS, 2017, 199 :88-92
[16]   Scripting-customised microscopy tools for Digital MicrographTM [J].
Mitchell, DRG ;
Schaffer, B .
ULTRAMICROSCOPY, 2005, 103 (04) :319-332
[17]  
Najib L.M., 2015, P INT CIV INFR ENG, P779, DOI [10.1007/978-981-287-290-6_67, DOI 10.1007/978-981-287-290-6_67]
[18]   Resolving the geometrically necessary dislocation content by conventional electron backscattering diffraction [J].
Pantleon, W. .
SCRIPTA MATERIALIA, 2008, 58 (11) :994-997
[19]   Heat transfer and fluid flow during keyhole mode laser welding of tantalum, Ti-6Al-4V, 304L stainless steel and vanadium [J].
Rai, R. ;
Elmer, J. W. ;
Palmer, T. A. ;
DebRoy, T. .
JOURNAL OF PHYSICS D-APPLIED PHYSICS, 2007, 40 (18) :5753-5766
[20]   Influence of grain shape and orientation on the mechanical properties of high pressure torsion deformed nickel [J].
Rathmayr, Georg B. ;
Hohenwarter, Anton ;
Pippan, Reinhard .
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING, 2013, 560 :224-231