Open Access. Powered by Scholars. Published by Universities.®
Articles 1 - 7 of 7
Full-Text Articles in Engineering
Corrosion And Passivation Behavior Of Laser Powder Bed Fusion Produced Ti-6al-4v Under Various Prior Plastic Deformation Strains, P. Qin, L. Y. Chen, Y. J. Liu, S. X. Liang, H. Sun, L. C. Zhang
Corrosion And Passivation Behavior Of Laser Powder Bed Fusion Produced Ti-6al-4v Under Various Prior Plastic Deformation Strains, P. Qin, L. Y. Chen, Y. J. Liu, S. X. Liang, H. Sun, L. C. Zhang
Research outputs 2022 to 2026
This work investigated the corrosion behavior of LPBF-produced Ti-6Al-4V under varying compression strains in a 3.5 wt% NaCl solution. It identifies that increasing compression strain causes significant alterations in the acicular a'-Ti phase (coarsening, breakage, and further coarsening). Corrosion resistance decreases with higher strains due to deformed a'-Ti phases, leading to increased film growth kinetics (from 0.09× 10−10 cm2/s increase to 12.75 × 10−10 cm2/s). Samples under higher strains (e.g., 32%) exhibit fluctuations in corrosion behavior due to initiated cracks and subsequent crevice corrosion. These findings are vital for understanding LPBF-produced Ti-6Al-4V in applications requiring mechanical strength and corrosion resilience.
Understanding Melt Pool Characteristics In Laser Powder Bed Fusion: An Overview Of Single- And Multi-Track Melt Pools For Process Optimization, Jincheng Wang, Rui Zhu, Yujing Liu, Laichang Zhang
Understanding Melt Pool Characteristics In Laser Powder Bed Fusion: An Overview Of Single- And Multi-Track Melt Pools For Process Optimization, Jincheng Wang, Rui Zhu, Yujing Liu, Laichang Zhang
Research outputs 2022 to 2026
Laser powder bed fusion (LPBF) has made significant progress in producing solid and porous metal parts with complex shapes and geometries. However, LPBF produced parts often have defects (e.g., porosity, residual stress, and incomplete melting) that hinder its large-scale industrial commercialization. The LPBF process involves complex heat transfer and fluid flow, and the melt pool is a critical component of the process. The melt pool stability is a critical factor in determining the microstructure, mechanical properties, and corrosion resistance of LPBF produced metal parts. Furthermore, optimizing process parameters for new materials and designed structures is challenging due to the complexity …
Response Of The Metastable Pitting Corrosion Of Laser Powder Bed Fusion Produced Ti–6al–4v To H+ Concentration Changes, Yuwei Cui, Liangyu Chen, Liqiang Wang, Jun Cheng, Laichang Zhang
Response Of The Metastable Pitting Corrosion Of Laser Powder Bed Fusion Produced Ti–6al–4v To H+ Concentration Changes, Yuwei Cui, Liangyu Chen, Liqiang Wang, Jun Cheng, Laichang Zhang
Research outputs 2022 to 2026
There is limited research on metastable pitting corrosion in an acidic environment, and acid is a major challenge for material corrosion. Therefore, this work investigated the metastable pitting corrosion of laser powder bed fusion (LPBF)-produced Ti–6Al–4V, in Hank’s solution, at different pH values (pH = 3, 5, and 7). This work investigated the effect of acid on the characteristics of passive films, as well as the change in metastable pitting behavior. Based on the results of electrochemical impedance spectroscopy (EIS) and X-ray photoelectron spectroscopy (XPS), the passive film will be inhibited and dissolved under the influence of H+. The higher …
Heterogeneous Microstructure And Mechanical Behaviour Of Al-8.3fe-1.3v-1.8si Alloy Produced By Laser Powder Bed Fusion, S. J. Yu, P. Wang, H. C. Li, R. Setchi, M. W. Wu, Z. Y. Liu, Z. W. Chen, S. Waqar, Lai-Chang Zhang
Heterogeneous Microstructure And Mechanical Behaviour Of Al-8.3fe-1.3v-1.8si Alloy Produced By Laser Powder Bed Fusion, S. J. Yu, P. Wang, H. C. Li, R. Setchi, M. W. Wu, Z. Y. Liu, Z. W. Chen, S. Waqar, Lai-Chang Zhang
Research outputs 2022 to 2026
The relationship between processing parameters, microstructure, and mechanical properties of Al-8.3Fe-1.3V-1.8Si alloy processed by laser powder bed fusion is seldom studied. Therefore, fully dense alloys with two parameters were selected to investigate this key issue. The results show that the alloy with low power and scanning speed (S200) shows fan-shell-shaped melt pools and laser tracks while another (S350) shows a deeper and wider melt pool. Both alloys obtain a heterogeneous microstructure without a secondary phase in melt pool (MP) and a nano-sized phase in melt pool boundary (MPB). The difference between solid-solution strengthening and Orowan strengthening in MP and MPB …
Corrosion Behavior And Mechanisms Of The Heat-Treated Ti5cu Produced By Laser Powder Bed Fusion, Xin Wang, Peng Qin, L. Y. Chen, Hongqi Sun, Laichang Zhang
Corrosion Behavior And Mechanisms Of The Heat-Treated Ti5cu Produced By Laser Powder Bed Fusion, Xin Wang, Peng Qin, L. Y. Chen, Hongqi Sun, Laichang Zhang
Research outputs 2022 to 2026
This work investigated the corrosion behavior of laser powder bed fusion produced (LPBFed) Ti5Cu and its heat-treated counterparts at 740 and 900 °C (named as HT-740 and HT-900 respectively) in Hank’s solution. The results indicated that the presence of acicular a'-Ti phase in LPBFed Ti5Cu was beneficial to corrosion, but the corrosion resistance of HT-740 and HT-900 were increased owing to the dual-phase microstructure (a'/a-Ti + Ti2Cu) or the increased content of Ti2Cu phase in the microstructure. The Ti2Cu phase could provide an ‘envelope’ protection to the a'/a-Ti phase and slow down the micro-galvanic reaction between a'/a-Ti phase and Ti2Cu …
Strong And Ductile Al–Mn–Mg–Sc–Zr Alloy Achieved In Fabrication-Rate Enhanced Laser Powder Bed Fusion, Hao Zhang, Lai Chang Zhang, Hongyu Liu, Xiaodong Niu, Marcus C. Lam, Wenzhe Zhang, Xiaojie Jin, Fuzhong Chu, Xinhua Wu, Sheng Cao
Strong And Ductile Al–Mn–Mg–Sc–Zr Alloy Achieved In Fabrication-Rate Enhanced Laser Powder Bed Fusion, Hao Zhang, Lai Chang Zhang, Hongyu Liu, Xiaodong Niu, Marcus C. Lam, Wenzhe Zhang, Xiaojie Jin, Fuzhong Chu, Xinhua Wu, Sheng Cao
Research outputs 2022 to 2026
The high cost of laser powder bed fusion (LPBF) fabricated high-strength Sc containing aluminium alloy hinders its applications. To reduce the cost, we reported a LPBF fabricated strong and ductile Al–Mn–Mg–Sc–Zr alloy using large layer thicknesses to improve the fabrication efficiency on coarse powder particles. A high relative density exceeding 99.2% was achieved at layer thicknesses up to 120 μm. In post-process heat-treated specimens, the yield strength only had a slight 6% decrease from layer thickness of 30 to 120 μm; such a decrease in strength was attributed to the larger grain size resulted from the adopted larger layer thickness. …
Corrosion Behavior And Mechanism Of Laser Powder Bed Fusion Produced Cocrw In An Acidic Nacl Solution, P. Qin, L. Y. Chen, Y. J. Liu, C. H. Zhao, Hongqi Sun, Laichang Zhang
Corrosion Behavior And Mechanism Of Laser Powder Bed Fusion Produced Cocrw In An Acidic Nacl Solution, P. Qin, L. Y. Chen, Y. J. Liu, C. H. Zhao, Hongqi Sun, Laichang Zhang
Research outputs 2022 to 2026
The corrosion behavior and mechanism of the laser powder bed fusion (L-PBF) produced CoCrW were investigated in 0.9 wt% NaCl solution with a pH of 2. The corrosion resistance of the alloy increases after 28 days of immersion because of the formed oxide film, which results in the increased corrosion potential and the decreased passivation current density on the potentiodynamic polarization test. The corrosion mechanism of the L-PBF-produced CoCrW could be explained by the melt pool formed from the laser melting process, that the melt pools were “shrinking” by the formation and dissolution of the oxide film.