scholarly journals Particle Erosion Induced Phase Transformation of Different Matrix Microstructures of Powder Bed Fusion Ti-6Al-4V Alloy Flakes

Metals ◽  
2019 ◽  
Vol 9 (7) ◽  
pp. 730 ◽  
Author(s):  
Jun-Ren Zhao ◽  
Fei-Yi Hung ◽  
Truan-Sheng Lui
Keyword(s):  
Phase Transformation ◽  
Particle Diameter ◽  
Powder Bed Fusion ◽  
Particle Erosion ◽  
Powder Bed ◽  
Α Phase ◽  
Heat Treated ◽  
Softened Zone ◽  
Strength And Ductility ◽  
Sequential Formation

In this study, powder bed fusion Ti-6Al-4V alloy flake was subjected to heat treatment at 800 °C for 4 h for inducing the complete transformation of the α’ phase into the α+β phases. An erosion experiment with 450 µm mean particle diameter of Al2O3 particles at a 90° impact on both the as- powder bed fusion (PBF) Ti-6Al-4V and the 4-h 800 °C heat-treated specimens to clarify the particle erosion-induced phase transformation behavior and its effect on mechanical properties. Particle erosion-induced phase transformation to the α phase was observed on both the as-PBF Ti-6Al-4V and the heat-treated specimens. It brought about a sequential formation from the surface to the bottom: (1) a surface softened zone, (2) a hardened zone, and (3) a hardness stabilization zone. The as-PBF Ti-6Al-4V was positively eroded by erosion particles, decreasing strength and ductility. In the case of the heat-treated specimens, we found decreased strength yet an increased ductility.

The role of texturing and microstructure evolution on the tensile behavior of heat-treated Inconel 625 produced via laser powder bed fusion

2020 ◽  
Vol 769 ◽  
pp. 138500 ◽  
Author(s):  
Giulio Marchese ◽  
Simone Parizia ◽  
Masoud Rashidi ◽  
Abdollah Saboori ◽  
Diego Manfredi ◽  
...  
Keyword(s):  
Microstructure Evolution ◽  
Tensile Behavior ◽  
Inconel 625 ◽  
Powder Bed Fusion ◽  
Laser Powder Bed Fusion ◽  
Powder Bed ◽  
Heat Treated

scholarly journals Analysis of the phase transformation of AlSi10Mg during Laser Powder Bed Fusion

Procedia CIRP ◽  
2020 ◽  
Vol 94 ◽  
pp. 177-181
Author(s):  
Andreas Wimmer ◽  
Maja Lehmann ◽  
Adrian Schuler ◽  
Michael F. Zaeh
Keyword(s):  
Phase Transformation ◽  
Powder Bed Fusion ◽  
Laser Powder Bed Fusion ◽  
Powder Bed

scholarly journals Fatigue Improvement of AlSi10Mg Fabricated by Laser-Based Powder Bed Fusion through Heat-Treatment.

2021 ◽  
Author(s):  
Felix Sajadi ◽  
Jan-Marc Tiemann ◽  
Nooshin Bandari ◽  
Ali Cheloee Darabi ◽  
Javad Mola ◽  
...  
Keyword(s):  
Heat Treatment ◽  
Fatigue Behavior ◽  
Fatigue Properties ◽  
Powder Bed Fusion ◽  
Microstructural Characteristics ◽  
Powder Bed ◽  
Treated Condition ◽  
Heat Treated ◽  
Treatment Parameter ◽  
Heat Treated Condition

This study aims to identify an optimal heat-treatment parameter set for an additively manufactured AlSi10Mg alloy in terms of increasing the hardness and eliminating the anisotropic microstructural characteristics of the alloy in as-built condition. Furthermore, the influence of these optimized parameters on the fatigue properties of the alloy investigated. In this respect, microstructural characteristics of an AlSi10Mg alloy manufactured by Laser-Based Powder Bed Fusion in non-heat-treated and heat-treated conditions were investigated. Their static and dynamic mechanical properties were evaluated, and fatigue behavior was explained by a detailed examination of fracture surfaces. Much of the microstructure in the non-heat-treated condition was composed of columnar grains oriented parallel to the build direction. Further analysis revealed a high fraction of pro-eutectic α-Al. Through heat-treatment, the alloy was successfully brought to its peak-hardened condition, while eliminating the anisotropic microstructural features. Yield strength and ductility increased simultaneously after heat-treatment, which is due to the relief of residual stresses, preservation of refined grains, and introduction of precipitation strengthening. The fatigue strength, calculated at 10^7 cycles, improved as well after heat-treatment and finally detailed fractography reviled that a more ductile fracture mechanism has happened in the heat-treated condition compared to the non-heat-treated condition.

scholarly journals Short Heat Treatments for the F357 Aluminum Alloy Processed by Laser Powder Bed Fusion

Materials ◽  
2021 ◽  
Vol 14 (20) ◽  
pp. 6157
Author(s):  
Matteo Vanzetti ◽  
Enrico Virgillito ◽  
Alberta Aversa ◽  
Diego Manfredi ◽  
Federica Bondioli ◽  
...  
Keyword(s):  
Heat Treatment ◽  
Precipitation Hardening ◽  
Solution Treatment ◽  
Heat Treatments ◽  
Point Of View ◽  
Powder Bed Fusion ◽  
Laser Powder Bed Fusion ◽  
Powder Bed ◽  
Heat Treated ◽  
Direct Aging

Conventionally processed precipitation hardening aluminum alloys are generally treated with T6 heat treatments which are time-consuming and generally optimized for conventionally processed microstructures. Alternatively, parts produced by laser powder bed fusion (L-PBF) are characterized by unique microstructures made of very fine and metastable phases. These peculiar features require specifically optimized heat treatments. This work evaluates the effects of a short T6 heat treatment on L-PBF AlSi7Mg samples. The samples underwent a solution step of 15 min at 540 °C followed by water quenching and subsequently by an artificial aging at 170 °C for 2–8 h. The heat treated samples were characterized from a microstructural and mechanical point of view and compared with both as-built and direct aging (DA) treated samples. The results show that a 15 min solution treatment at 540 °C allows the dissolution of the very fine phases obtained during the L-PBF process; the subsequent heat treatment at 170 °C for 6 h makes it possible to obtain slightly lower tensile properties compared to those of the standard T6. With respect to the DA samples, higher elongation was achieved. These results show that this heat treatment can be of great benefit for the industry.

Dynamic-loading behavior and anisotropic deformation of pre- and post-heat-treated IN718 fabricated by laser powder bed fusion

2020 ◽  
Vol 33 ◽  
pp. 101083 ◽  
Author(s):  
Nadia Kouraytem ◽  
Raphaël A. Chanut ◽  
Dillon S. Watring ◽  
Timmanee Loveless ◽  
John Varga ◽  
...  
Keyword(s):  
Dynamic Loading ◽  
Powder Bed Fusion ◽  
Laser Powder Bed Fusion ◽  
Powder Bed ◽  
Heat Treated ◽  
Anisotropic Deformation

scholarly journals Laser Powder Bed Fusion of Inconel 718: Residual Stress Analysis Before and After Heat Treatment

Metals ◽  
2019 ◽  
Vol 9 (12) ◽  
pp. 1290 ◽  
Author(s):  
Rafael Barros ◽  
Francisco J. G. Silva ◽  
Ronny M. Gouveia ◽  
Abdollah Saboori ◽  
Giulio Marchese ◽  
...  
Keyword(s):  
Heat Treatment ◽  
Lateral Surface ◽  
Extreme Temperature ◽  
Hole Drilling ◽  
Powder Bed Fusion ◽  
Laser Powder Bed Fusion ◽  
Powder Bed ◽  
Tensile Stresses ◽  
Compressive Stresses ◽  
Heat Treated

Residual stresses (RS) of great magnitude are usually present in parts produced by Laser Powder Bed Fusion (PBF-LB), mainly owing to the extreme temperature gradients and high cooling rates involved in the process. Those “hidden” stresses can be detrimental to a part’s mechanical properties and fatigue life; therefore, it is crucial to know their magnitude and orientation. The hole-drilling strain-gage method was used to determine the RS magnitude and direction-depth profiles. Cuboid specimens in the as-built state, and after standard solution annealing and ageing heat treatment conditions, were prepared to study the RS evolution throughout the heat treatment stages. Measurements were performed on the top and lateral surfaces. In the as-built specimens, tensile stresses of ~400 MPa on the top and above 600 MPa on the lateral surface were obtained. On the lateral surface, RS anisotropy was noticed, with the horizontally aligned stresses being three times lower than the vertically aligned. RS decreased markedly after the first heat treatment. On heat-treated specimens, magnitude oscillations were observed. By microstructure analysis, the presence of carbides was verified, which is a probable root for the oscillations. Furthermore, compressive stresses immediate to the surface were obtained in heat-treated specimens, which is not in agreement with the typical characteristics of parts fabricated by PBF-LB, i.e., tensile stresses at the surface and compressive stresses in the part’s core.

Sign in / Sign up

Export Citation Format

Share Document