Carlos Rojas

Mr. Carlos Rojas

orcid

Research Focus & Metrics

Academic Career Length

9Years (2018-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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7 January 2021 in Metals
Verified
Journal Article
Open access
PDF file
VTVictor Tuninetti
Victor Tuninetti
AJAndres Jaramillo
Andres Jaramillo
GPGuiomar Riu Perdrix
Guiomar Riu Perdrix
CRCarlos Rojas
Carlos Rojas
AZAmna Znaidi
Amna Znaidi
Joan Josep Roa RoviraJoan Josep Roa Rovira
Joan Josep Roa Rovira
This article focuses on a systematic study of a Ti-6Al-4V alloy in order to extensively characterize the main mechanical properties at the macro-, micro- and submicrometric length scale under different stress fields. Hardness, elastic modulus, true stress–strain curves and strain-hardening exponent are correlated with the intrinsic properties of the α- and β-phases that constitute this alloy. A systematic characterization process followed, considering the anisotropic effect on both orthogonal crystallographic directions, as well as determining the intrinsic properties for the α-phase. An analytical relationship was established between the flow stress determined under different stress fields, testing geometries and length scales, highlighting that it is possible to estimate flow stress under compression and/or tensile loading from the composite hardness value obtained by instrumented nanoindentation testing.

15 November 2018 in Nanoscale Advances
Verified
Journal Article
Open access
PDF file
MOMário César Albuquerque de Oliveira
Mário César Albuquerque de Oliveira
LMLeonardo Menezes
Leonardo Menezes
PPPablo I. R. Pincheira
Pablo I. R. Pincheira
CRCarlos Rojas
Carlos Rojas
NGNikifor Rakov Gomez
Nikifor Rakov Gomez
AGAnderson Stevens Leônidas Gomes
Anderson Stevens Leônidas Gomes
Electrospun fiber-based random lasers are environment-friendly flexible systems in which waveguiding/scattering processes provided by their structure with a broad distribution of diameters are essential elements to generate a suitable lasing mechanism.

7 April 2024 in Aerospace
Verified
Journal Article
Open access
PDF file
VTVictor Tuninetti
Victor Tuninetti
HSHéctor Sepúlveda
Héctor Sepúlveda
CBCarlos Beecher
Carlos Beecher
CRCarlos Rojas
Carlos Rojas
AOAngelo Oñate
Angelo Oñate
MVMarian Valenzuela
Marian Valenzuela
Finite element modeling for designing and optimizing lightweight titanium aerospace components requires advanced simulation tools with adequate material modeling. In this sense, a hybrid strategy is proposed in this work to identify the parameters of the Johnson–Cook plasticity and damage laws using a combined direct-inverse method. A direct calibration method for plasticity law is applied based on the literature-reported data of strain-stress curves from experimental tensile tests at different temperatures and strain rates. The triaxiliaty-dependent fracture parameters of the Johnson–Cook damage law at reference conditions of strain rate and temperature (d1, d2, and d3) are calibrated with the direct method based on new data of experimental evolution of computed average fracture strain with the average stress triaxiality. The validation is performed with numerical results from an accurate micromechanics-based Ti64 model. The inverse calibration method is used to determine the strain rate and temperature-dependent damage parameters (d4 and d5) through large strain simulations of uniaxial tensile tests. The numerical results, including average strain and necking profile at fracture, are then utilized to calculate stress triaxiality by the Bridgman criterion for adjusting parameters d4 and d5. The calibrated model yields a 2.1% error for plasticity and 3.4% for fracture predictions. The experimental and simulated load-bearing capacity using the micromechanics damage model differed by only 1%. This demonstrates that the SC11–TNT model of Ti64 is reliable for identifying the Johnson–Cook damage law through the accurate use of inverse methods. The hybrid calibration strategy demonstrates the potential capability of the identified Johnson–Cook model to accurately predict the design load-carrying capacity of Ti64 aerospace components under different deformation rates and temperatures while accounting for material damage effects.

1 May 2019 in Optical Materials
Verified
Journal Article
Closed access
JSJuliana Mikaelly Dias Soares
Juliana Mikaelly Dias Soares
LMLeonardo de Souza Menezes
Leonardo de Souza Menezes
PPPablo I.R. Pincheira
Pablo I.R. Pincheira
CRCarlos Rojas
Carlos Rojas
NGNikifor Rakov Gomez
Nikifor Rakov Gomez
AGAnderson Stevens Leônidas Gomes
Anderson Stevens Leônidas Gomes

3 March 2024 in Materials at High Temperatures
Verified
Journal Article
Closed access
CRCarlos Rojas
Carlos Rojas
HMH. Morch
H. Morch
VTV. Tuninetti
V. Tuninetti
JTJ. Tchoufang Tchuindjang
J. Tchoufang Tchuindjang
OPO. Pensis
O. Pensis
AHA.M. Habraken
A.M. Habraken

15 December 2023 in Computers & Mathematics with Applications
Verified
Journal Article
Closed access
CRCarlos Rojas
Carlos Rojas
HMHélène Morch
Hélène Morch
VTVíctor Tuninetti
Víctor Tuninetti
LDLaurent Duchêne
Laurent Duchêne
AHAnne Habraken
Anne Habraken