Mechanism of pore evolution in electron beam welding joints of Mo-14Re alloy
Source abstract
Abstract
The mechanism of pore evolution in vacuum electron beam joints of Mo-14Re alloy has been thoroughly investigated. Microscopic characterization methods, including Optical Microscopy (OM) and Scanning Electron Microscopy (SEM), were employed to explore the evolution mechanism of pore defects at different locations. Weld defects were further characterized using Energy Dispersive Spectroscopy (EDS) and Transmission Electron Microscopy (TEM), providing insights into their formation mechanisms. The findings reveal that pores along grain boundaries are the result of MoO and CO bubble aggregation. Non-equilibrium solidification of the melt triggers chemical reactions, transforming MoO and CO bubbles into MoO3 and C, with lower melting points. MoO3 and C persist in the pores, leading to the formation of grain boundary gas hole defects. On the other hand, intragranular pore defects stem from an abundance of pores within the matrix material. Upon entry of gas from these pores into the molten pool, its escape is impeded due to the intense influence of the molten pool. After the molten pool completes the cooling and solidification process, the gas remains within the crystal, resulting in intragranular pore defects.
Source: openalex_inverted_index · Quality: baseline
Research context
OpenAlex topics: Intermetallics and Advanced Alloy Properties · Advanced materials and composites · Titanium Alloys Microstructure and Properties
SciVX discovery tags are terminology-based. OpenAlex topics are source-provided classifications.
References (18)
Show source-provided references
1. A novel method for preparing ultrafine molybdenum-rhenium alloy powders10.1016/j.ijrmhm.2023.106429 ↗
2. Research on high-temperature mechanical properties and microstructure of powder metallurgical rhenium10.1016/j.ijrmhm.2022.105861 ↗
3. Parametric optimization of multi-pass electron beam melting for molybdenum alloy containing 47.5 wt% rhenium10.1016/j.ijrmhm.2023.106193 ↗
4. The tensile response of Mo, Mo–Re and Mo–Si solid solutions10.1016/j.ijrmhm.2013.05.005 ↗
5. Microstructural characterization and mechanical properties of additively manufactured molybdenum and molybdenum alloys
6. Microstructure and mechanical properties of supersonic plasma sprayed Mo-based coating reinforced by Re10.1016/j.surfcoat.2019.124966 ↗
7. Thermophysical properties of refractory W-50.4%Re and Mo-39.5%Re thin alloy layers deposited on silicon and silica substrates10.1016/j.ijrmhm.2019.105147 ↗
8. Cyclic tensile response of Mo-27 at% Re and Mo-0.3 at% Si solid solution alloys10.1016/j.msea.2016.08.114 ↗
9. Hot compression behaviors and microstructural evolution of Mo-42 wt%Re alloy10.1016/j.matlet.2022.132252 ↗
10. Regulation of performance of laser-welded socket joint of Mo–14Re ultra-high-temperature heat pipe by introducing Ti into both weld and heat affected zone10.1016/j.jmrt.2022.11.162 ↗
11. Modelling of thermal behaviour in niobium during electron beam welding
12. Temperature-gradient induced microstructure evolution in heat-affected zone of electron beam welded Ti-6Al-4V titanium alloy10.1016/j.jmst.2019.04.004 ↗
13. Study on microstructure and performance of molybdenum joint welded by electron beam10.1016/j.vacuum.2018.04.031 ↗
14. Microstructure evolution and embrittlement of electron beam welded TZM alloy joint10.1016/j.msea.2017.05.076 ↗
15. Microstructure transformation and pore formation mechanism of Mo-14Re alloy weld by vacuum electron beam welding10.1016/j.vacuum.2023.112594 ↗
16. Microstructural evolution and mechanical properties of bulk and porous low-cost Ti–Mo–Fe alloys produced by powder metallurgy10.1016/j.jallcom.2020.156768 ↗
17. The microstructure analysis, mechanical properties, and fracture behavior of electron beam welded C-103 niobium-based refractory alloy10.1016/j.jmrt.2023.05.070 ↗
18. Barin · 2008