title: Structural characterization of biomedical Co-Cr-Mo components produced by direct metal laser sintering.
abstract: Direct metal laser sintering (DMLS) is a technique to manufacture complex functional mechanical parts from a computer-aided design (CAD) model. Usually, the mechanical components produced by this procedure show higher residual porosity and poorer mechanical properties than those obtained by conventional manufacturing techniques. In this work, a Co-Cr-Mo alloy produced by DMLS with a composition suitable for biomedical applications was submitted to hardness measurements and structural characterization. The alloy showed a hardness value remarkably higher than those commonly obtained for the same cast or wrought alloys. In order to clarify the origin of this unexpected result, the sample microstructure was investigated by X-ray diffraction (XRD), electron microscopy (SEM and TEM) and energy dispersive microanalysis (EDX). For the first time, a homogeneous microstructure comprised of an intricate network of thin ε (hcp)-lamellae distributed inside a γ (fcc) phase was observed. The ε-lamellae grown on the {111}γ planes limit the dislocation slip inside the γ (fcc) phase, causing the measured hardness increase. The results suggest possible innovative applications of the DMLS technique to the production of mechanical parts in the medical and dental fields.
authors.affiliation: SIMAU, Università Politecnica delle Marche, via Brecce Bianche, 60131 Ancona, Italy. Electronic address: g.barucca@univpm.it.
authors.forename: G
authors.initials: G
authors.lastname: Barucca
authors.affiliation: SIMAU, Università Politecnica delle Marche, via Brecce Bianche, 60131 Ancona, Italy.
authors.forename: E
authors.initials: E
authors.lastname: Santecchia
authors.affiliation: SIMAU, Università Politecnica delle Marche, via Brecce Bianche, 60131 Ancona, Italy.
authors.forename: G
authors.initials: G
authors.lastname: Majni
authors.affiliation: DISCO, Università Politecnica delle Marche, via Brecce Bianche, 60131 Ancona, Italy.
authors.forename: E
authors.initials: E
authors.lastname: Girardin
authors.affiliation: DIMeC, University of Modena and Reggio Emilia, via Vignolese 905/B, Modena 41125, Italy.
authors.forename: E
authors.initials: E
authors.lastname: Bassoli
authors.affiliation: DIMeC, University of Modena and Reggio Emilia, via Vignolese 905/B, Modena 41125, Italy.
authors.forename: L
authors.initials: L
authors.lastname: Denti
authors.affiliation: DIMeC, University of Modena and Reggio Emilia, via Vignolese 905/B, Modena 41125, Italy.
authors.forename: A
authors.initials: A
authors.lastname: Gatto
authors.affiliation: DISPEA, Politecnico di Torino, C.so Duca degli Abruzzi 24, 10129 Torino, Italy.
authors.forename: L
authors.initials: L
authors.lastname: Iuliano
authors.affiliation: Faculty of Metals Engineering and Industrial Computer Science, AGH University of Science and Technology, Al. Mickiewicza 30, 30-059 Kraków, Poland.
authors.forename: T
authors.initials: T
authors.lastname: Moskalewicz
authors.affiliation: SIMAU, Università Politecnica delle Marche, via Brecce Bianche, 60131 Ancona, Italy.
authors.forename: P
authors.initials: P
authors.lastname: Mengucci
mesh_terms: D002858:Chromium Alloys / Q000737:chemistry*; D003035:Cobalt / Q000737:chemistry*; D006244:Hardness; D007834:Lasers; D008855:Microscopy, Electron, Scanning; D046529:Microscopy, Electron, Transmission; D008982:Molybdenum / Q000737:chemistry; D013672:Technology / Q000379:methods*; D014961:X-Ray Diffraction
chemical_list: D002858:Chromium Alloys; D003035:Cobalt; D008982:Molybdenum
keywords: Laser processing; Metals and alloys; Scanning electron microscopy, SEM; Sintering; Transmission electron microscopy, TEM; X-ray diffraction