Experimental study of inclusions in CP-Ti EB ingot by electrolytic extraction
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摘要: 采用电子束冷床炉(EBCHM)熔炼的TA2轧制酸洗卷常出现表面起皮缺陷。针对这一现象,研究通过电解法得到了TA2铸锭中的夹杂物,采用SEM-EDS研究了夹杂物的三维形貌、种类及尺寸分布并分析其来源。基于C语言建立了钛氧化物夹杂的溶解模型,分析了其去除机理和影响因素。结果表明,TA2铸锭中的夹杂物以钛氧化物为主,占比86.84%,以及少量的Al2O3、复合夹杂和高密度夹杂,夹杂尺寸大多分布在80~300 μm;钛氧化物在溶解的过程中表层会发生相变,生成Ti3O5相薄层,在
1720 ℃下,直径500 μm的TiO2完全溶解需要466.67 s。铸锭内夹杂物的含量与轧制表面质量呈反比,提升熔体温度和降低熔炼速率有利于提升铸锭纯净度和轧制表面的质量。Abstract: The TA2 rolled and pickled coils produced by electron beam cold hearth melting (EBCHM) often exhibits surface peeling defects. To address this issue, this study extracted inclusions from TA2 ingots via electrolytic extraction and investigated their three-dimensional morphology, type, and size distribution using SEM-EDS, while their origins were also analyzed. A dissolution model for titanium oxides inclusion was developed using C code, and the removal mechanism and influencing factors were analyzed. Titanium oxides accounts for 86.84% of the inclusions in the ingots, followed by smaller quantities of Al2O3, composite inclusions, and high-density inclusions. The inclusion sizes predominantly range from 80 μm to 300 μm. During dissolution, the surface layer of titanium oxides undergoes phase transformation, forming a thin Ti3O5 layer. At1720 ℃ , complete dissolution of a 500 μm TiO2 particle requires 466.67 s. The content of inclusions in the ingot is inversely proportional to the rolling surface quality. Increasing the melting temperature and reducing the melting rate are beneficial to improving the purity of the ingot and the rolling surface quality.-
Key words:
- TA2 pure titanium /
- inclusions /
- surface peeling defects /
- hot-rolled coils /
- electrolytic extraction
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表 1 不同炉号的原料配比
Table 1. The raw material ratio of different heat numbers
No. Raw material 1# Grade 2 and above sponge titanium + Grade 5 sponge
titanium + debris + TiO2 powder2# Grade 2 and above sponge titanium + Grade 5 sponge
titanium + debris表 2 1#与2#的电解结果
Table 2. Electrolysis results of 1# and 2#
Sample Electrolytic
weight/kgInclusion
weight/mgNormalized weight/
(mg·kg-1)Inclusion particle size classification/(µm·mg−1) <80 80~140 140~300 >300 1# 1.321 1.5 4.043 0.3 0.9 0.3 2# 0.335 0.8 2.388 0.5 0.3 表 3 夹杂物元素含量
Table 3. Elemental content of inclusions
% C O Al Si Mg Ti Fe Cr Co Ni W Titanium
oxide7.68 43.9 48.42 Al2O3 6.66 45.13 42.16 6.05 Complex
inclusions9.1 49.5 8.96 29.39 2.15 0.89 FexOy 13.85 26.56 1.62 56.54 1.44 High-density
inclusions8.73 13.28 2.43 6.44 1.45 21.01 32.57 14.09 表 4 1#与2#中夹杂物种类及数量占比
Table 4. Types and quantity proportions of inclusions in 1# and 2#
Inclusion type Quantity/count Proportion/% 1# 2# Sum Titanium oxide 17 16 33 86.84 High-density inclusions 1 0 1 2.6 Al2O3 0 1 1 2.6 Complex inclusions 0 3 3 7.9 表 5 对照组和试验组的酸洗缺陷统计
Table 5. Statistics of pickling defects in control group and experimental group
No. First pickling defects /(Count·m−1) Second pickling defects /(Count·m−1) Upper surface Lower surface Upper surface Lower surface Control group
(Without TiO2 addition)E1117-2 0.293 0.48 0.505 0.253 E1117-1 0.59 1.98 0.257 1.264 E1114-1 0.727 0.58 1.333 0.887 E1115-1 0.41 1.72 0.1 2.35 E1115-2 0.06 1.73 0.115 3.308 Average/m 0.416 1.298 4.62 1.6124 Test group
(With TiO2 addition)E1012-2 1.74 2.65 1.284 3.105 E1011-2 1.243 2.96 1.02 2.52 E1008-2 1.535 2.769 1.316 4.003 E1010-2 1.449 2.841 1.236 2.48 Average/m 1.492 2.805 1.214 3.027 -
[1] CUI Y, SUN X J, ZHANG Z B, et al. Microstructure evolution during hot rolling of TA1 slab produced by EB furnace smelting[J]. Iron Steel Vanadium Titanium, 2020, 41(3): 53-58. (崔岩, 孙新军, 张志波, 等. EB炉熔炼TA1铸坯在热轧过程中的组织演变[J]. 钢铁钒钛, 2020, 41(3): 53-58. doi: 10.7513/j.issn.1004-7638.2020.03.008CUI Y, SUN X J, ZHANG Z B, et al. Microstructure evolution during hot rolling of TA1 slab produced by EB furnace smelting[J]. Iron Steel Vanadium Titanium, 2020, 41(3): 53-58. doi: 10.7513/j.issn.1004-7638.2020.03.008 [2] TRUONG V D, HYUN Y T, WON J W, et al. Numerical simulation of the effects of scanning strategies on the aluminum evaporation of titanium alloy in the electron beam cold hearth melting process[J]. Materials, 2022, 15(3): 820. doi: 10.3390/ma15030820 [3] GAO L, HUANG H G, ZAHNG Y Q, et al. Numerical modeling of EBCHM for large-scale TC4 alloy round ingots[J]. JOM, 2018, 70(12): 2934-2942. doi: 10.1007/s11837-018-3048-0 [4] SEMIATIN S L, KOBRYN P A, IVASISHIN O M. The role of modeling in the development of advanced processes for metallic aerospace alloys[J]. Metals and Materials International, 2004, 10(6): 589-603. doi: 10.1007/BF03027423 [5] MIAO Z H, CHANG L, ZHOU C Y, et al. Study on the biaxial tensile behavior of commercial pure titanium at room temperature[J]. Iron Steel Vanadium Titanium, 2024, 45(4): 41-47. (苗自豪, 常乐, 周昌玉, 等. 工业纯钛室温双轴拉伸力学行为研究[J]. 钢铁钒钛, 2024, 45(4): 41-47. doi: 10.7513/j.issn.1004-7638.2024.04.007MIAO Z H, CHANG L, ZHOU C Y, et al. Study on the biaxial tensile behavior of commercial pure titanium at room temperature[J]. Iron Steel Vanadium Titanium, 2024, 45(4): 41-47. doi: 10.7513/j.issn.1004-7638.2024.04.007 [6] AN Z S, CHEN Y, ZHAO W, et al. 2023 China titanium industry development report[J] Iron Steel Vanadium Titanium, 2024, 45(3): 1-8. (安仲生, 陈岩, 赵巍, 等. 2023年中国钛工业发展报告[J]. 钢铁钒钛, 2024, 45(3): 1-8.AN Z S, CHEN Y, ZHAO W, et al. 2023 China titanium industry development report[J] Iron Steel Vanadium Titanium, 2024, 45(3): 1-8. [7] DONG F Y, LIU F, SHEN X Y, et al. Development status of high-entropy alloy powder preparation and applications[J]. China Powder Science and Technology, 2025, 31(6): 1-15. (董福宇, 刘峰, 申向阳, 等. 高熵合金粉体制备及应用的发展现状[J]. 中国粉体技术, 2025, 31(6): 1-15. doi: 10.13732/j.issn.1008-5548.2025.06.007DONG F Y, LIU F, SHEN X Y, et al. Development status of high-entropy alloy powder preparation and applications[J]. China Powder Science and Technology, 2025, 31(6): 1-15. doi: 10.13732/j.issn.1008-5548.2025.06.007 [8] ZHANG C H, ZHENG M, WANG Y M, et al. Effect of high energy shot peening on the wear resistance of TiN films on a TA2 surface[J]. Surface & Coatings Technology, 2019, 378: 124821-124821. doi: 10.1016/j.surfcoat.2019.07.045 [9] CHENG J. Study on cold deformation, phase transformation and corrosion behavior of a new metastable β-type Ti-B12 biomedical titanium alloy[D]. Xi’an: Northwestern Polytechnical University, 2021. (程军. 新型亚稳定β型Ti-B12医用钛合金冷变形、相变与腐蚀行为研究[D]. 西安: 西北工业大学, 2021.CHENG J. Study on cold deformation, phase transformation and corrosion behavior of a new metastable β-type Ti-B12 biomedical titanium alloy[D]. Xi’an: Northwestern Polytechnical University, 2021. [10] WU W Y, SONG C H, ZHANG Z S, et al. Microstructure and properties of as-cast Co-28Cr alloy with aging treatment[J]. Chinese Journal of Rare Metals, 2025, 49(7): 982-990. (吴文源, 宋成浩, 张振山, 等. 时效处理对铸态Co-28Cr合金组织和性能的影响[J]. 稀有金属, 2025, 49(7): 982-990.WU W Y, SONG C H, ZHANG Z S, et al. Microstructure and properties of as-cast Co-28Cr alloy with aging treatment[J]. Chinese Journal of Rare Metals, 2025, 49(7): 982-990. [11] ZHU J L, CHENG J, CHEN L Y. Research status of heat treatment for laser powder bed fusion of Ti-6Al-4V: Microstructure evolution and corrosion resistance[J]. Chinese Journal of Engineering, 2024, 46(8): 1393-1402. (朱金岭, 程军, 陈靓瑜. 激光粉床熔融Ti-6Al-4V热处理的研究现状: 微观组织演变和耐腐蚀性能[J]. 工程科学学报, 2024, 46(8): 1393-1402. doi: 10.13374/j.issn2095-9389.2023.10.23.001ZHU J L, CHENG J, CHEN L Y. Research status of heat treatment for laser powder bed fusion of Ti-6Al-4V: Microstructure evolution and corrosion resistance[J]. Chinese Journal of Engineering, 2024, 46(8): 1393-1402. doi: 10.13374/j.issn2095-9389.2023.10.23.001 [12] ZHANG J Q, ZHANG M Y, SONG Y X, et al. Formation mechanism of surface defect and its influence on microstructure and properties of pure titanium plate[J]. Nonferrous Metal Materials and Engineering, 2024, 45(6): 68-74. (张俊祺, 张明玉, 宋一新, 等. 纯钛板表面缺陷形成机制以及对组织性能的影响[J]. 有色金属材料与工程, 2024, 45(6): 68-74.ZHANG J Q, ZHANG M Y, SONG Y X, et al. Formation mechanism of surface defect and its influence on microstructure and properties of pure titanium plate[J]. Nonferrous Metal Materials and Engineering, 2024, 45(6): 68-74. [13] LEE H, CHOI M. Study on edge cracking of titanium cold rolled sheet[J]. MATEC Web of Conferences, 2020, 321. [14] BELLOT P J, DEFAY B, JOURDAN J, et al. Inclusion behavior during the electron beam button melting test[J]. Journal of Materials Engineering and Performance, 2012, 21(10): 2140-2146. doi: 10.1007/s11665-012-0153-z [15] ZHANG Y M, ZHOU L, SUN J, et al. An investigation on electron beam cold hearth melting of Ti64 alloy[J]. Rare Metal Materials and Engineering, 2008, 37(11): 1973-1977. doi: 10.1016/S1875-5372(10)60004-5 [16] GAO L, HUANG H G, JIANG Y H, et al. Numerical study on the solid–liquid interface evolution of large-scale titanium alloy ingots during high energy consumption electron beam cold hearth melting[J]. JOM, 2020, 72(5): 1953-1960. doi: 10.1007/s11837-020-04089-5 [17] CEN M J, LIU Y, CHEN X. Inclusions in melting process of titanium and titanium alloys[J]. China Foundry, 2019, 16(4): 223-231. doi: 10.1007/s41230-019-9046-1 [18] BELLOT P J, ABLITZER D, FOSTER B, et al. Dissolution of hard-alpha inclusions in liquid titanium alloys[J]. Metallurgical and Materials Transactions B, 1997, 28(6): 1001-1010. doi: 10.1007/s11663-997-0054-y [19] GHAZAL G, CHAPELLE P, JARDY A, et al. Dissolution of high density inclusions in titanium alloys[J]. ISIJ International, 2012, 52(1): 1-9. doi: 10.2355/isijinternational.52.1 [20] LI X A, WANG N, CHEN M, et al. Tracking large-size inclusions in Al deoxidated tinplate steel in industrial practice: steelmaking[J]. ISIJ International, 2021, 61(7): 2074-2082. doi: 10.2355/isijinternational.ISIJINT-2020-679 [21] YAN W, XU H C, CHEN W Q. Study on inclusions in wire rod of tire cord steel by means of electrolysis of wire rod[J]. steel research international, 2014, 85(1): 53-59. doi: 10.1002/srin.201300045 [22] FUNAGANE H. Electron beam melting toward inclusion-free titanium alloys[J]. IOP Conference Series: Materials Science and Engineering, 2018, 424. [23] LI Y, WANG L, WANG Y, et al. Study on flow, heat transfer and volatilization behavior of molten titanium in cold hearth during EB furnace melting process[J]. Titanium Industry Progress, 2023, 40(4): 6-12. (李阳, 王力, 王运, 等. EB炉冷床内钛液流动、传热和挥发行为研究[J]. 钛工业进展, 2023, 40(4): 6-12.LI Y, WANG L, WANG Y, et al. Study on flow, heat transfer and volatilization behavior of molten titanium in cold hearth during EB furnace melting process[J]. Titanium Industry Progress, 2023, 40(4): 6-12. -
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