Effects of scanning strategy during powder bed fusion electron beam additive manufacturing (PBF-EB AM) on microstructure, nano-mechanical properties, and creep behavior of Ti6Al4V alloys were compared. Results show that PBF-EB AM Ti6Al4V alloy with linear scanning without rotation strategy was composed of 96.9% α-Ti and 2.7% β-Ti, and has a nanoindentation range of 4.11-6.31 GPa with the strain rate ranging from 0.001 to 1 s, and possesses a strain-rate sensitivity exponent of 0.053 ± 0.014. While PBF-EB AM Ti6Al4V alloy with linear and 90° rotate scanning strategy was composed of 98.1% α-Ti and 1.9% β-Ti and has a nanoindentation range of 3.98-5.52 GPa with the strain rate ranging from 0.001 to 1 s, and possesses a strain-rate sensitivity exponent of 0.047 ± 0.009. The nanohardness increased with increasing strain rate, and creep displacement increased with the increasing maximum holding loads. The creep behavior was mainly dominated by dislocation motion during deformation induced by the indenter. The PBF-EB AM Ti6Al4V alloy with only the linear scanning strategy has a higher nanohardness and better creep resistance properties than the alloy with linear scanning and 90° rotation strategy. These results could contribute to understanding the creep behavior of Ti6Al4V alloy and are significant for PBF-EB AM of Ti6Al4V and other alloys.
Download full-text PDF |
Source |
---|---|
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8199181 | PMC |
http://dx.doi.org/10.3390/ma14113004 | DOI Listing |
Materials (Basel)
January 2025
Faculty of Materials Science and Technology, VŠB-Technical University of Ostrava, 17. listopadu 2172/15, 708 00 Ostrava, Czech Republic.
This paper summarizes the results of investigations into heterogeneous P23/P91 welds after long-term creep exposure at temperatures of 500, 550 and 600 °C. Two variants of welds were studied: In Weld A, the filler material corresponded to P91 steel, while in Weld B, the chemical composition of the consumable material matched P23 steel. The creep rupture strength values of Weld A exceeded those of Weld B at all testing temperatures.
View Article and Find Full Text PDFMaterials (Basel)
December 2024
National Key Laboratory for Precision Hot Processing of Metals, Harbin Institute of Technology, Harbin 150001, China.
In this study, a (TiB + TiC + YO)/α-Ti composite was prepared by induction skull melting to investigate its creep behavior and microstructure evolution under different temperatures and stresses. The results show that the microstructure of the composite in the as-cast state is a basket-weave structure, and the main phase composition is α lamella, containing a small amount of β phase and equiaxed α phase. The creep life of the composite decreases significantly when the temperature is increased from 650 °C to 700 °C, and the steady-state creep rate is increased by 1 to 2 orders of magnitude.
View Article and Find Full Text PDFMaterials (Basel)
December 2024
Department of Civil Engineering, Gyeongsang National University, Jinju 52828, Republic of Korea.
Corrosion in reinforced concrete (RC) structures has led to the increased adoption of non-corrosive materials, such as carbon fiber-reinforced polymers (CFRPs), as replacements for traditional steel rebar. However, ensuring the long-term reliability of CFRP grids under sustained stress is critical for achieving safe and effective designs. This study investigates the long-term tensile creep rupture behavior of CFRP grids to establish a design threshold for their tensile strength under sustained loading conditions in demanding structural applications.
View Article and Find Full Text PDFSci Rep
January 2025
Institute of the Malay World and Civilisation (ATMA), Universiti Kebangsaan Malaysia (UKM), 43600, Bangi, Selangor, Malaysia.
The adoption of pultruded glass fibre-reinforced polymer (pGFRP) composites as a substitute for traditional wooden cross-arms in high transmission towers represents a relatively novel approach. These materials were selected for their high strength-to-weight ratio and lightweight properties. Despite various studies focusing on structures improvement, there still have a significant gap in understanding the deformation characteristics of full-scale cross-arms under actual operational loads.
View Article and Find Full Text PDFEur Phys J E Soft Matter
January 2025
Soft Matter Science and Engineering (SIMM), ESPCI Paris, PSL University, Sorbonne Université, CNRS, Rue Vauquelin, 75005, Paris, France.
The creep behavior of an amorphous poly(etherimide) polymer is investigated in the vicinity of its glass transition in a weakly non linear regime where the acceleration of the creep response is driven by local configurational rearrangements. From the time shifts of the creep compliance curves under stresses from 1 to 15 MPa and in the temperature range between and , where is the glass transition temperature, we determine a macroscopic acceleration factor. The macroscopic acceleration is shown to vary as temperature with , where is the macroscopic stress and Y is a decreasing function of compliance.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!