Tailoring alloy 718 laser directed energy deposition process strategies for repair applications

2022 ◽  
Vol 34 (1) ◽  
pp. 012018
Author(s):  
Cory D. Jamieson ◽  
Marissa C. Brennan ◽  
Todd J. Spurgeon ◽  
Stephen W. Brown ◽  
Jayme S. Keist ◽  
...  
Metals ◽  
2020 ◽  
Vol 10 (10) ◽  
pp. 1280
Author(s):  
Pedro Ramiro ◽  
Mikel Ortiz ◽  
Amaia Alberdi ◽  
Aitzol Lamikiz

In this study, a manufacturing strategy, and guidelines for inclined and multilayered structures of variable thickness are presented, which are based on the results of an own-developed geometrical model that obtains both the coating thickness and dilution. This model is developed for the powder-fed directed energy deposition process (DED) and it only uses the DED single-track cladding characteristics (height, width, area, and dilution depth), the overlap percentage, and the laser head tilting-angle as inputs. As outputs, it calculates both the cladding geometry and the dilution area of the coating. This model for the Ni-based alloy 718 was improved, based on previous studies of the single clad working both vertically and at an inclined angle, adding the equations of the single clad characteristics with respect to the main process parameters. The strategy proposed in this paper for multilayered cladding consisted of both adding an extra clad at the edges of the layer and using a variable value of the overlap percentage between clads for geometric adaptations. With this strategy, the material deposition is more accurate than otherwise, and it shows stable growth. Manufacturing a multilayered wall of wider thicknesses at higher heights was utilized to validate the strategy.


2020 ◽  
Vol 26 ◽  
pp. 1108-1112 ◽  
Author(s):  
B.N. Manjunath ◽  
A.R. Vinod ◽  
K. Abhinav ◽  
S.K. Verma ◽  
M. Ravi Sankar

2019 ◽  
Vol 62 (4) ◽  
pp. 213-217 ◽  
Author(s):  
Abdollah Saboori ◽  
Sara Biamino ◽  
Mariangela Lombardi ◽  
Simona Tusacciu ◽  
Mattia Busatto ◽  
...  

Author(s):  
Jianyi Li ◽  
Qian Wang ◽  
Panagiotis (Pan) Michaleris

In modeling and simulating thermo-mechanical behavior in a directed energy deposition process, it often needs to compute the temperature field evolved in the deposition process since thermal history in the deposition process would affect part geometry as well as microstructure, material properties, residual stress, and distortion of the final part. This paper presents an analytical computation of temperature field evolved in a directed energy deposition process, using a single-bead wall as an illustrating example. Essentially, the temperature field is computed by superposition of the temperature fields generated by the laser source as well as induced from each of the past beads, where the transient solution to a moving heat source in a semi-infinite body is applied to describe each individual temperature field. For better characterization of cooling effect (temperature contribution from a past bead), a pair of positive and negative virtual heat sources is assigned for each past bead. In addition, mirrored heat sources through a reflexion technique are introduced to define the adiabatic boundaries of the part being built and to account for the substrate thickness. In the end, three depositions of Ti-6AL-4V walls with different geometries and inter-layer dwell times on an Optomec® laser engineered net shaping (LENS) system are used to validate the proposed analytical computation, where predicted temperatures at several locations of the depositions show reasonable agreement with the in situ temperature measurements, with the average prediction error less than 15%. The proposed analytical computation for temperature field in directed energy deposition could be potentially used in model-based feedback control for thermal history in the deposition, which could affect microstructure evolution and other properties of the final part.


Procedia CIRP ◽  
2020 ◽  
Vol 88 ◽  
pp. 393-398
Author(s):  
Gabriele Piscopo ◽  
Eleonora Atzeni ◽  
Alessandro Salmi ◽  
Luca Iuliano ◽  
Andrea Gatto ◽  
...  

Sign in / Sign up

Export Citation Format

Share Document