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Tong JB, Zhang CJ, Chen JS, Yan MQ, Xu RL, Huang LJ. Effects of Homogenization Heat Treatment on the Fe Micro-Segregation in Ti-1023 Titanium Alloy. MATERIALS (BASEL, SWITZERLAND) 2023; 16:4911. [PMID: 37512186 PMCID: PMC10381604 DOI: 10.3390/ma16144911] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/30/2023] [Revised: 07/06/2023] [Accepted: 07/07/2023] [Indexed: 07/30/2023]
Abstract
The segregation of the Fe element in Ti-10V-2Fe-3Al titanium alloy (Ti-1023) can lead to the generation of beta flecks, which seriously affects the performance of Ti-1023 products. During the heat treatment (HT) process at a high temperature, the Fe element in Ti-1023 ingots will migrate, making its distribution more uniform and reducing the segregation index. In this paper, the control of Fe micro-segregation in Ti-1023 ingots by homogenization HT was investigated. Firstly, dissection sampling and SEM-EDS analysis methods were used to study the distribution pattern of the Fe element in the equiaxed grains in the core of Ti-1023 ingots. It was found that the Fe content in the grain gradually increased along with the radial direction from the core to the grain boundary. Then, the homogenization HT experiments and numerical simulations of Ti-1023 at different HT temperatures from 1050 °C to 1200 °C were carried out. The results showed that the uniformity of Fe element distribution within grain can be significantly improved by the homogenization HT. With increasing HT temperature, Fe atoms migration ability increases, and the uniformity of Fe element distribution improves. Homogenization HT at 1150 °C and 1200 °C for 12 h can effectively reduce the degree of Fe element segregation.
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Affiliation(s)
- Jian-Bo Tong
- Aviation Key Laboratory of Science and Technology on Advanced Titanium Alloys, AECC Beijing Institute of Aeronautical Materials, Beijing 100095, China
| | - Chao-Jie Zhang
- School of Metallurgical Engineering, Anhui University of Technology, Ma'anshan 243002, China
| | - Jun-Shu Chen
- Aviation Key Laboratory of Science and Technology on Advanced Titanium Alloys, AECC Beijing Institute of Aeronautical Materials, Beijing 100095, China
| | - Meng-Qi Yan
- Aviation Key Laboratory of Science and Technology on Advanced Titanium Alloys, AECC Beijing Institute of Aeronautical Materials, Beijing 100095, China
| | - Rui-Lin Xu
- Aviation Key Laboratory of Science and Technology on Advanced Titanium Alloys, AECC Beijing Institute of Aeronautical Materials, Beijing 100095, China
| | - Li-Jun Huang
- Aviation Key Laboratory of Science and Technology on Advanced Titanium Alloys, AECC Beijing Institute of Aeronautical Materials, Beijing 100095, China
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Kim DH, Heo JH, Park HS, Kim JK, Park JH. Improving the production efficiency of high-titania slag in Ti extraction process: fluxing effect on formation of pseudobrookite. Sci Rep 2020; 10:6530. [PMID: 32300163 PMCID: PMC7162870 DOI: 10.1038/s41598-020-63532-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2019] [Accepted: 03/31/2020] [Indexed: 11/23/2022] Open
Abstract
We investigated the carbothermic reduction process of ilmenite ore at 1873 K with flux addition. Without flux, the pseudobrookite phase with a high melting temperature was precipitated during ilmenite smelting. This could be the main reason for decreased reduction of iron in ilmenite. To accelerate reduction of ilmenite, two factors were considered. One is increasing the reduction driving force during smelting. Activity of FeO is the major factor to control reduction in driving force. The other factor is delay in formation of the pseudobrookite phase, a high-melting point precipitation phase. In this system, MgO in ilmenite could be used to form pseudobrookite. To control these factors, in this study, flux agent (i.e., Na2O or SiO2) addition was considered. The thermochemical simulation program, FactSageTM7.0 was used to calculate the viscosity of slag and the activity of components as fluxing agents were added. High-temperature experiments using an induction furnace were also conducted to confirm the computational results. To determine the composition of final products, i.e., titanium slag, X-ray fluorescence analysis was executed. As a result of Fe and Ti behaviours in slag, SiO2 addition showed no significant difference from the slag without flux. However, Fe reduction in ilmenite, i.e. TiO2-enrichment, was more accelerated when Na2O was added. X-ray diffraction, scanning electron microscopic and transmission electron microscopic analyses results also showed that even 1 wt% Na2O addition significantly influenced the titanium slag production compared to no flux addition.
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Affiliation(s)
- Dong Hyeon Kim
- Department of Materials Engineering, Hanyang University, Ansan, 15588, Korea.,Research and Development Center, Dongkuk Steel, Pohang, 37873, Korea
| | - Jung Ho Heo
- Department of Materials Engineering, Hanyang University, Ansan, 15588, Korea.,Research and Development Center, LS-Nikko Copper, Ulsan, 44997, Korea
| | - Hyun Sik Park
- Resources Recovery Research Center, Korea Institute of Geoscience and Mineral Resources (KIGAM), Daejeon, 34121, Korea
| | - Jin Kyung Kim
- Department of Materials Engineering, Hanyang University, Ansan, 15588, Korea
| | - Joo Hyun Park
- Department of Materials Engineering, Hanyang University, Ansan, 15588, Korea. .,Department of Materials Science and Engineering, KTH Royal Institute of Technology, Stockholm, 100 44, Sweden.
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