scholarly journals Utilização da técnica de difração de raios-X para o estudo de amostras de Ti-6Al-4V forjadas e fabricadas por fusão seletiva a laser

2019 ◽  
Vol 40 ◽  
pp. 249
Author(s):  
Max Amorim Brum ◽  
Fábio Beck ◽  
Oreci Escobar da Silva ◽  
Gustavo Luiz Callegari ◽  
Marcos André Carara ◽  
...  
Keyword(s):  
Residual Stresses ◽  
Selective Laser Melting ◽  
Structural Characteristics ◽  
Lattice Parameter ◽  
Manufacturing Processes ◽  
X Ray Diffraction ◽  
Laser Melting ◽  
Engineering Project ◽  
X Ray ◽  
Great Relevance

The search for materials with well-defined characteristics is very important for any engineering project. In addition, it is known that the various types of manufacturing processes directly influence in properties of the parts. In this work, the X-ray diffraction technique was used to study the structural characteristics of Ti-6Al-4V samples manufactured by the forging and Selective Laser Melting techniques. We found that the samples made by FSL were able to present a reduction of 1% in the lattice parameter perpendicular to the studied plane, when compared with the forged samples. Since most of the parts manufactured by Selective Laser Melting meet the demands of aeronautical and aerospace projects, where residual stresses are generally undesirable for making the parts more fragile, studies like these acquire great relevance.

scholarly journals Evaluation of Weld Filler Alloying Concepts for Residual Stress Engineering by Means of Neutron and X-Ray Diffraction

2014 ◽  
Vol 996 ◽  
pp. 469-474 ◽  
Author(s):  
Arne Kromm
Keyword(s):  
Residual Stress ◽  
Residual Stresses ◽  
Stress Reduction ◽  
Maximum Stress ◽  
Lattice Parameter ◽  
Filler Materials ◽  
X Ray Diffraction ◽  
X Ray ◽  
Stress Control ◽  
Surface Areas

Novel Low Transformation Temperature (LTT-) filler materials are specially designed for controlling residual stresses by means of adjusted martensite formation already during welding. Different alloying concepts compete for maximum stress reduction. Two newly developed LTT-alloys were evaluated concerning their potential for residual stress control. For this purpose residual stresses were determined in the surface and also in sub-surface areas of welded joints using X-ray diffraction and Neutron diffraction taking into account local variations of the unstrained lattice parameter.

scholarly journals Determination of Residual Stresses in an Oxidized Metallic Alloy under Thermal Loadings

Metals ◽  
2018 ◽  
Vol 8 (11) ◽  
pp. 913
Author(s):  
Zhimao Wang ◽  
Jean-Luc Grosseau-Poussard ◽  
Benoît Panicaud ◽  
Guillaume Geandier ◽  
Pierre-Olivier Renault ◽  
...  
Keyword(s):  
Residual Stresses ◽  
Correction Method ◽  
Lattice Parameter ◽  
European Synchrotron Radiation Facility ◽  
X Ray Diffraction ◽  
Synchrotron Diffraction ◽  
X Ray ◽  
Crystallographic Planes

In order to clarify the mechanical features of a metal under thermal cyclic loading for the system Ni30Cr-Cr2O3, a specific study has been carried out. In the present work, the residual stresses in both the metal and the oxide layer have been investigated. An adapted method is applied to process the experimental results that were obtained by using in-situ high temperature synchrotron diffraction at European Synchrotron Radiation Facility. The sin2ψ analysis provides information about the stress in metal and oxide. X-ray diffraction provides also the lattice parameter between crystallographic planes in the metal. To obtain correct stress values, a correction method is also proposed taking into account different discrepancies sources to ensure the equation of mechanical balance.

scholarly journals A miniaturized selective laser melting device for operando X-ray diffraction studies

2020 ◽  
Vol 34 ◽  
pp. 101194 ◽  
Author(s):  
Samy Hocine ◽  
Steven Van Petegem ◽  
Ulrich Frommherz ◽  
Gemma Tinti ◽  
Nicola Casati ◽  
...  
Keyword(s):  
Selective Laser Melting ◽  
X Ray Diffraction ◽  
Laser Melting ◽  
X Ray

A Comparison of X-Ray and Neutron Diffraction Measurement of Lattice Parameters for the Determination of Residual Stress and Chemical Composition in Zirconium Alloy Tubes

1991 ◽  
Vol 35 (A) ◽  
pp. 475-480
Author(s):  
M. Griffiths ◽  
J.E. Winegar ◽  
J.F. Mecke ◽  
T.M. Holden ◽  
R.A. Holt
Keyword(s):  
Residual Stress ◽  
Neutron Diffraction ◽  
Residual Stresses ◽  
Zirconium Alloys ◽  
Lattice Parameter ◽  
Lattice Parameters ◽  
Surface Relaxation ◽  
Chemical Compositions ◽  
X Ray Diffraction ◽  
X Ray

AbstractIntergranular residual stresses can exist in zirconium alloys, especially when there is a large distribution of grain orientations. The stresses result from the anisotropic plasticity and thermal expansion of the hexagonal close-packed crystal structure of α-zirconium. Apart from complicating the characterisation of materials using lattice parameter measurements, the intergranular stresses can significantly affect material behaviour, especially in nuclear reactor environments, and there is therefore a great deal of interest in their measurement.The effects of specimen preparation and surface relaxation on X-ray diffraction measurements of lattice parameters of zirconium alloys have been investigated by comparing bulk neutron diffraction with X-ray diffraction on identical materials. The results show that: (i) intergranular or interphase residual stresses exist in dual-phase Zr-2.5Nb pressure tubes; (ii) the stresses normal to the surface of an X-ray diffraction specimen are not relieved completely when there are intergranular residual stresses in the material. One can conclude that intergranular stresses have to be considered when determining chemical compositions from lattice parameter measurements and also when measuring macroscopic residual stress using X-ray diffraction.

Effect of boronizing on the structural, mechanical and tribological properties of CoCrW dental alloy produced by selective laser melting

2019 ◽  
Vol 71 (3) ◽  
pp. 348-356
Author(s):  
Yakup Uzun ◽  
Halim Kovacı ◽  
Ali Fatih Yetim ◽  
Ayhan Çelik
Keyword(s):  
Selective Laser Melting ◽  
Tribological Properties ◽  
Surface Characteristics ◽  
Production Method ◽  
Dental Alloy ◽  
X Ray Diffraction ◽  
Laser Melting ◽  
Content Type ◽  
X Ray ◽  
Mechanical And Tribological Properties

PurposeThis paper aims to investigate the effects of boriding on the structural, mechanical and tribological properties of CoCrW dental alloy manufactured by the method of selective laser melting.Design/methodology/approachIn this study, CoCrW alloy samples that are used in dentistry were manufactured by the method of laser melting, and boriding treatment was made on the samples at 900°C and 1,000°C for 1, 4 and 8 h. The structural, mechanical and tribological effects of boriding on the samples were analyzed using X-ray diffraction, scanning electron microscopy, energy dispersive X-ray spectroscopy, microhardness and an abrasion test device.FindingsAccording to the results, the best outcomes in terms of abrasion strength and hardness were obtained in the sample that was subjected to boriding at 1,000°C for 4 h.Originality/valueThis study produced CoCrW alloys, which are fundamental biomaterials that are used in dentistry, by a different production method called selective laser melting and improved their surface characteristics by boriding.

Experimental observation of stress formation during selective laser melting using in situ X-ray diffraction

2020 ◽  
Vol 32 ◽  
pp. 101028
Author(s):  
Felix Schmeiser ◽  
Erwin Krohmer ◽  
Norbert Schell ◽  
Eckart Uhlmann ◽  
Walter Reimers
Keyword(s):  
Experimental Observation ◽  
Selective Laser Melting ◽  
X Ray Diffraction ◽  
Laser Melting ◽  
X Ray ◽  
Stress Formation

scholarly journals Selective Laser Melting of Ti6Al4V-2%Hydroxyapatite Composites: Manufacturing Behavior and Microstructure Evolution

Metals ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 1295
Author(s):  
Hassanen Jaber ◽  
János Kónya ◽  
Tünde Anna Kovács
Keyword(s):  
Mechanical Properties ◽  
Tensile Properties ◽  
Selective Laser Melting ◽  
Tensile Testing ◽  
X Ray Diffraction ◽  
Laser Melting ◽  
Biological Fixation ◽  
X Ray ◽  
Composites Manufacturing ◽  
Scanning Electron

In this work, selective laser melting of Ti6Al4V (Ti64) and 2 wt.% hydroxyapatite (HA) composites was performed with the purpose of osseointegration enhancement and biological fixation between implants and bone tissue. The microstructural evolution and mechanical properties were analyzed by using X-ray diffraction (XRD), optical microscopy (OM), a scanning electron microscope (SEM) equipped with (EDX) and (EBSD) systems, microhardness, nanoindentation, and tensile testing. The results showed that the Ti64-2%HA composite components exhibited complicated manufacturing behavior, which could be correlated with the decomposition of HA. The microstructure was found to mainly consist of α Ti with a small amount of HA distributed along grain boundaries. Furthermore, the interaction between Ti64 and HA leading to the formation of Ti3P, TixO, P, and CaTiO3 phases, resulted in poor tensile properties, as compared to pure Ti64 components. Conversely, the tensile properties of SLM Ti64-2%HA composite components were significantly higher than human bone reported previously in the literature.

scholarly journals A Comprehensive Study of Steel Powders (316L, H13, P20 and 18Ni300) for Their Selective Laser Melting Additive Manufacturing

Metals ◽  
2019 ◽  
Vol 9 (1) ◽  
pp. 86 ◽  
Author(s):  
Jujie Yan ◽  
Yinghao Zhou ◽  
Ruinan Gu ◽  
Xingmin Zhang ◽  
Wai-Meng Quach ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Surface Structure ◽  
Oxide Layer ◽  
Selective Laser Melting ◽  
Photoelectron Spectroscopy ◽  
Raw Material ◽  
Powder Materials ◽  
X Ray Diffraction ◽  
Laser Melting ◽  
X Ray

The determination of microstructural details for powder materials is vital for facilitating their selective laser melting (SLM) process. Four widely used steels (316L, H13, P20 and 18Ni300) have been investigated to detail their powders’ microstructures as well as laser absorptivity to understand their SLM processing from raw material perspective. Phase components of these four steel powders were characterized by X-ray diffraction (XRD), synchrotron radiation X-ray diffraction (SR-XRD) and scanning electron microscopy (SEM). X-ray photoelectron spectroscopy (XPS) and transmission electron microscopy (TEM) were utilized to reveal the surface structure of these four steel powders. It is found that phase components of H13, P20 and 18Ni300 are mainly composed of martensite and a small amount of austenite due to the high cooling rate during gas atomization processing, while 316L is characterized by austenite. XPS results show that the four steel powders all possess a layered surface structure, consisting of a thin iron oxide layer at the outmost surface and metal matrix at the inner surface. It is found that the presence of such oxide layer can improve the absorptivity of steel powders and is beneficial for their SLM process.

Residual Stresses in Ultrathin Metal Sublayers Within Au/Ni Multilayers

1997 ◽  
Vol 475 ◽  
Author(s):  
S. Labat ◽  
P. Gergaud ◽  
O. Thomas ◽  
B. Gilles ◽  
A. Marty ◽  
...  
Keyword(s):  
Residual Stress ◽  
Residual Stresses ◽  
Residual Strain ◽  
Strain State ◽  
Lattice Parameter ◽  
Metallic Multilayers ◽  
X Ray Diffraction ◽  
X Ray ◽  
Residual Strains ◽  
Far From Equilibrium

ABSTRACTMetallic Multilayers (MLs) have attracted a considerable interest during these last years because of their unusual properties. In small periods ML's (a few nm) the high density of interfaces give rise to structures very far from equilibrium. Au/Ni multilayers have been grown in the (111) orientation by M.B.E. on Si(100) via a Cu(100) buffer layer. Two different parameters have been studied: the Au:Ni ratio at constant (4 nm) superperiod and the superperiod at constant (1:1) Au:Ni ratio. The full strain state of Au and of Ni has been determined via x-ray diffraction measurements. The high lattice parameter misfit beween Au and Ni (14%) implies that all the layers are partially relaxed. Residual strains as high as several % are encountered. The residual strain in the Au layers is clearly correlated with their thickness. A residual stress as high as 3.9 GPa is determined in the thinner layers.

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