臺灣博碩士論文加值系統

Al0.3CrFe1.5MnNi0.5 高熵合金藉由析出介金屬相具有良好時效強度，但經均質化處理後仍無法消除其 BCC 結構，使其加工性受限。本研究藉由調整成份使均質化處理後合金能維持單一 FCC 結構，並額外添加 TiC、Ti、Mo 產生不同類型之析出物，探討時效處理後不同析出物形貌對於機械性質之影響。實驗結果顯示介金屬析出物經 100 小時時效仍能維持其硬度，其中添加 Ti 之合金藉由 B2、L12、η 析出相硬度可由Hv 120 提升至 Hv 500。
此外，本研究將四款合金之時效態進行高溫磨耗試驗，並與商用熱作模具鋼 SKD61 進行比較，結果顯示四款合金具有優異之抗氧化性，四者摩擦係數僅0.1~0.3，均優於 SKD61，材料成本方面也與 SKD61 相近，證實高熵合金在較低成本之高溫材料應用端也具一定潛力。

Al0.3CrFe1.5MnNi0.5 high entropy alloy has significant age-hardening by precipitation of intermetallic phase. However, the BCC structure couldn’t be eliminated after being homogenized, which limit the workability of this alloy. This study designs the as-homogenized state with FCC structure by adjusting the composition with the addition of titanium carbide, titanium and molybdenum, and investigates the effect of precipitates after aging treatment on the mechanical properties. The results show that hardness of the alloys remains at the same level after aging for 100 hours. The hardness of the alloy with addition of titanium increases from Hv 120 to Hv 500 with the precipitation of B2, L12 and η phase.
The high-temperature wear performance of the present alloys is investigated, and compared with SKD61 steel further. The results show that the present alloys have excellent oxidation resistance and friction coefficient only about 0.1~0.3. The cost are also similar with SKD61 steel, which proves that high-entropy alloys have the potential in high-temperature applications.

致謝 I
摘要 V
Abstract VI
目錄 VII
圖目錄 XII
表目錄 XIX
壹、 前言 1
貳、 文獻回顧 3
2.1. 析出強化 3
2.2. 高熵合金的定義 6
2.3. 高熵合金四大核心效應 7
2.3.1. 高熵效應 (High-entropy effect) 7
2.3.2. 嚴重晶格應變效應 (Severe-lattice-distortion effect) 9
2.3.3. 遲緩擴散效應 (Sluggish-diffusion effect) 11
2.3.4. 雞尾酒效應 (Cocktail effect) 13
2.4. 高溫磨耗 14
2.4.1. 高溫磨耗行為 [18] 14
2.4.2. 影響磨耗性質之因素 16
2.4.3. 磨耗面之釉層種類 18
2.5. Al-Cr-Fe-Mn-Ni 高熵合金微結構與機械性質 23
2.5.1. Al-Cr-Fe-Mn-Ni 高熵合金變形與退火微結構探討 26
2.5.2. Al-Cr-Fe-Mn-Ni 高熵合金冷加工退火機械性質 26
2.5.3. Al-Cr-Fe-Mn-Ni 高熵合金冷加工退火微結構演變 28
2.6. Al-Cr-Fe-Mn-Ni 高熵合金成份調質微結構與機械性質分析 30
2.6.1. Al-Cr-Fe-Mn-Ni 系統單相高熵合金 30
2.6.2. Al-Cr-Fe-Mn-Ni 系統高熵合金 Al 變量以及 Mo 添加之影響 31
2.7. 高熵合金之 σ、η、TiC 相研究 33
2.7.1. σ 相與 ρ 相結構探討 33
2.7.2. σ 相於 Al-Cr-Fe-Mn-Ni 高熵合金之生成機制探討 35
2.7.3. η 相析結構探討 37
2.7.4. TiC 散佈強化探討 40
參、 研究方法 42
3.1. 實驗步驟 42
3.2. 實驗試片之製備 43
3.2.1. 真空電弧熔煉 43
3.2.2. 室溫冷滾軋加工 43
3.2.3. 均質化熱處理 44
3.2.4. 時效熱處理 44
3.3. 微結構與晶體結構分析 45
3.3.1. X光繞射分析 (XRD) 45
3.3.2. 蝕刻液 45
3.3.3. 掃描式電子顯微鏡 (SEM) 45
3.3.4. 穿透式電子顯微鏡 (TEM) 46
3.4. 其他性質分析與量測 47
3.4.1. Thermal-Calc 熱力學平衡模擬 47
3.4.2. 硬度分析 47
3.4.3. 高溫磨耗測試 48
肆、 結果與討論 49
4.1. 合金成份設計 49
4.1.1. 非等莫耳 AlCrFeMnNi 合金相模擬與統計參數 49
4.1.2. 非等莫耳 AlCrFeMnNi 合金改變Ni含量之微結構分析 52
4.1.3. 析出相模擬與合金設計 56
4.2. 合金之鑄造態、均質化態基本性質 59
4.2.1. 微結構觀察 59
4.2.2. 鑄造態與均質化硬度分析 63
4.2.3. 滾軋性質分析 64
4.3. 非等莫耳 AlCrFeMnNi 合金之時效態微結構與機械性質分析 65
4.3.1. 微結構觀察 65
4.3.2. TEM 微結構分析 70
4.3.3. 時效硬化曲線分析 73
4.4. 非等莫耳 AlCrFeMnNi 合金添加 TiC 之時效態性質分析 75
4.4.1. 微結構觀察 75
4.4.2. 時效硬化曲線分析 79
4.5. 非等莫耳 AlCrFeMnNi 合金添加 Ti 之時效態性質分析 80
4.5.1. 微結構觀察 80
4.5.2. 時效硬化曲線分析 87
4.6. 非等莫耳 AlCrFeMnNi 合金添加 Mo 之時效態性質分析 89
4.6.1. 微結構觀察 89
4.6.2. 時效硬化曲線分析 94
4.7. 高溫磨耗性質 95
4.7.1. 摩擦係數分析 95
4.7.2. 剖面氧化層與高溫磨耗機制分析 102
4.7.3. 比較商用合金 SKD61 117
伍、 結論 120
陸、 未來研究方向 122
柒、 參考文獻 123

[1] J. W. Yeh, S. K. Chen, S. J. Lin, J. Y. Gan, T. S. Chin, T. T. Shun, et al., "Nanostructured high-entropy alloys with multiple principal elements: Novel alloy design concepts and outcomes," Advanced Engineering Materials, vol. 6, pp. 299-303, May 2004.
[2] C.-W. Tsai, Y.-L. Chen, M.-H. Tsai, J.-W. Yeh, T.-T. Shun, and S.-K. Chen, "Deformation and annealing behaviors of high-entropy alloy Al0.5CoCrCuFeNi," Journal of Alloys and Compounds, vol. 486, pp. 427-435, 2009/11/03/ 2009.
[3] C.-W. Tsai, M.-H. Tsai, J.-W. Yeh, and C.-C. Yang, "Effect of temperature on mechanical properties of Al0.5CoCrCuFeNi wrought alloy," Journal of Alloys and Compounds, vol. 490, pp. 160-165, 2010/02/04/ 2010.
[4] 陳宣佑,"Al-Cr-Cu-Fe-Mn-Ni高熵合金變形及退火行為之研究." 國立清華大學, 2004.
[5] 郭彥甫,"Al-Cr-Fe-Mn-Ni高熵合金變形及退火行為之研究." 國立清華大學, 2005.
[6] M. H. Tsai, H. Yuan, G. M. Cheng, W. Z. Xu, W. W. W. Jian, M. H. Chuang, et al., "Significant hardening due to the formation of a sigma phase matrix in a high entropy alloy," Intermetallics, vol. 33, pp. 81-86, Feb 2013.
[7] 蔡宇翔,"AlxCrFe1.5MnNi0.5-(Mo, Cu)0.1(x= 0.15, 0.3, 0.4, 0.5) 高熵合金性質及微結構之研究." 國立清華大學, 2006.
[8] 蔡耀庭,"Al-Cr- Fe-Mn-Ni高熵合金冷加工及時效後微結構及性質之研究." 國立清華大學, 2006.
[9] G. E. Dieter,"Mechanical metallurgy," London ; New York : McGraw-Hill, 1988., 1988.
[10] R. Abbaschian,"Physical metallurgy principles," Stamford, CT : Cengage Learning, c2010., 2010.
[11] H. Gleiter and E. Hornbogen, "Precipitation hardening by coherent particles," Materials Science and Engineering, vol. 2, pp. 285-302, 1968/03/01 1968.
[12] Dislocations in solids," Amsterdam ; New York : North-Holland Pub. Co., 1979-<1996 >. 1979.
[13] J. W. Yeh, "Recent progress in high-entropy alloys," Annales De Chimie-Science Des Materiaux, vol. 31, pp. 633-648, Nov-Dec 2006.
[14] J. W. Yeh, S. K. Chen, J. Y. Gan, S. J. Lin, T. S. Chin, T. T. Shun, et al., "Formation of simple crystal structures in Cu-Co-Ni-Cr-Al-Fe-Ti-V alloys with multiprincipal metallic elements," Metallurgical and Materials Transactions a-Physical Metallurgy and Materials Science, vol. 35A, pp. 2533-2536, Aug 2004.
[15] Z. Wang, W. Qiu, Y. Yang, and C. T. Liu, "Atomic-size and lattice-distortion effects in newly developed high-entropy alloys with multiple principal elements," Intermetallics, vol. 64, pp. 63-69, 2015/09/01/ 2015.
[16] C. J. Tong, Y. L. Chen, S. K. Chen, J. W. Yeh, T. T. Shun, C. H. Tsau, et al., "Microstructure characterization of AlxCoCrCuFeNi high-entropy alloy system with multiprincipal elements," Metallurgical and Materials Transactions a-Physical Metallurgy and Materials Science, vol. 36A, pp. 881-893, Apr 2005.
[17] S. Ranganathan, "Alloyed pleasures: Multimetallic cocktails," Current Science, vol. 85, pp. 1404-1406, Nov 2003.
[18] 曾世凱,"鎳基合金在乾式磨耗條件下磨耗行為之探討," 義守大學, 2006.
[19] T. F. J. Quinn,"Physical Analysis for Tribology," Cambridge University Press, 2005.
[20] S. C. Lim, M. F. Ashby, and J. H. Brunton, "The effects of sliding conditions on the dry friction of metals," Acta Metallurgica, vol. 37, pp. 767-772, 1989/03/01/ 1989.
[21] F. H. Stott, D. S. Lin, and G. C. Wood, "The Structure and Mechanism of Formation if the Glaze Oxide Produced on Nickel-based Alloys During Wear at High Temperatures," Corrosion Science, vol. 13, pp. 449-469, 1973.
[22] J. Jiang, F. H. Stott, and M. M. Stack, "A generic model for dry sliding wear of metals at elevated temperatures," Wear, vol. 256, pp. 973-985, 2004/05/01/ 2004.
[23] K.-H. Zum Gahr,"Microstructure and wear of materials." vol. 10: Elsevier, 1987.
[24] S. C. Lim and M. F. Ashby, "Overview no. 55 wear-mechanism maps," Acta metallurgica, vol. 35, pp. 1-24, 1987.
[25] A. P. Sannino and H. J. Rack, "Dry sliding wear of discontinuously reinforced aluminum composites: review and discussion," Wear, vol. 189, pp. 1-19, 1995/10/01/ 1995.
[26] A. Pauschitz, M. Roy, and F. Franek, "Identification of the mechanisms of wear during sliding of metallic materials at elevated temperature using an optical interferometer," in Tribology Series. vol. 43, G. Dalmaz, A. A. Lubrecht, D. Dowson, and M. Priest, Eds., ed: Elsevier, 2003, pp. 721-730.
[27] A. Pauschitz, M. Roy, and F. Franek, "Vergleichende Untersuchung des Hochtemperatur-Verschleiss-Verhaltens von Chrom bei der Bildung von Legierungen auf Fe-und Ni-Basis," Tribologie und Schmierungstechnik, vol. 50, pp. 40-49, 2003.
[28] A. Pauschitz, M. Roy, and F. Franek, "Mechanisms of sliding wear of metals and alloys at elevated temperatures," Tribology International, vol. 41, pp. 584-602, 2008.
[29] L. C. Tsao, C. S. Chen, and C. P. Chu, "Age hardening reaction of the Al0.3CrFe1.5MnNi0.5 high entropy alloy," Materials & Design, vol. 36, pp. 854-858, Apr 2012.
[30] A. Blachowski, "Kinetics of the sigma-phase formation in an (Fe53.8 Cr46.2)-0.1at.% Ti alloy," Philosophical Magazine Letters, vol. 79, pp. 87-91, 1999/02/01 1999.
[31] D. M. E. Villanueva, F. C. P. Junior, R. L. Plaut, and A. F. Padilha, "Comparative study on sigma phase precipitation of three types of stainless steels: austenitic, superferritic and duplex," Materials Science and Technology, vol. 22, pp. 1098-1104, 2006/09/01 2006.
[32] S. M. Dubiel and J. Cieślak, "Sigma-Phase in Fe-Cr and Fe-V Alloy Systems and its Physical Properties," Critical Reviews in Solid State and Materials Sciences, vol. 36, pp. 191-208, 2011/10/01 2011.
[33] W. R. Wang, W. L. Wang, and J. W. Yeh, "Phases, microstructure and mechanical properties of AlxCoCrFeNi high-entropy alloys at elevated temperatures," Journal of Alloys and Compounds, vol. 589, pp. 143-152, Mar 2014.
[34] N. G. Jones, K. A. Christofidou, and H. J. Stone, "Rapid precipitation in an Al0.5CrFeCoNiCu high entropy alloy," Materials Science and Technology, vol. 31, pp. 1171-1177, 2015/07/01 2015.
[35] W. Liu, X.-G. Lu, P. Boulet, and M.-C. Record, "Influencing factors of atomic order in the binary sigma phase," Intermetallics, vol. 93, pp. 6-19, 2018/02/01/ 2018.
[36] J. C. Zhao, V. Ravikumar, and A. M. Beltran, "Phase precipitation and phase stability in Nimonic 263," Metallurgical and Materials Transactions a-Physical Metallurgy and Materials Science, vol. 32, pp. 1271-1282, Jun 2001.
[37] S. Q. Zhao, X. S. Xie, G. D. Smith, and S. J. Patel, "Microstructural stability and mechanical properties of a new nickelbased superalloy," Materials Science and Engineering a-Structural Materials Properties Microstructure and Processing, vol. 355, pp. 96-105, Aug 2003.
[38] N. D. Evans, P. J. Maziasz, R. W. Swindeman, and G. D. Smith, "Microstructure and phase stability in INCONEL alloy 740 during creep," Scripta Materialia, vol. 51, pp. 503-507, Sep 2004.
[39] S. Q. Zhao, X. H. Xie, G. D. Smith, and S. J. Patel, "Research and Improvement on structure stability and corrosion resistance of nickel-base superalloy INCONEL alloy 740," Materials & Design, vol. 27, pp. 1120-1127, 2006.
[40] Q. Y. Wu, H. J. Song, R. W. Swindeman, J. P. Shingledecker, and V. K. Vasudevan, "Microstructure of long-term aged IN617Ni-base superalloy," Metallurgical and Materials Transactions a-Physical Metallurgy and Materials Science, vol. 39A, pp. 2569-2585, Nov 2008.
[41] H. Leitner, M. Schober, and R. Schnitzer, "Splitting phenomenon in the precipitation evolution in an Fe-Ni-Al-Ti-Cr stainless steel," Acta Materialia, vol. 58, pp. 1261-1269, Feb 2010.
[42] K. Hagihara, T. Nakano, and Y. Umakoshi, "Plastic deformation behaviour in Ni3Ti single crystals with D024 structure," Acta Materialia, vol. 51, pp. 2623-2637, 2003/05/23/ 2003.
[43] H. Choi-Yim and W. L. Johnson, "Bulk metallic glass matrix composites," Applied physics letters, vol. 71, pp. 3808-3810, 1997.
[44] J. Eckert, J. Das, S. Pauly, and C. Duhamel, "Mechanical properties of bulk metallic glasses and composites," Journal of materials research, vol. 22, pp. 285-301, 2007.
[45] J. Schroers, G. Kumar, T. M. Hodges, S. Chan, and T. R. Kyriakides, "Bulk metallic glasses for biomedical applications," Jom, vol. 61, pp. 21-29, 2009.
[46] L. R. Katipelli, A. Agarwal, and N. B. Dahotre, "Laser surface engineered TiC coating on 6061 Al alloy: microstructure and wear," Applied Surface Science, vol. 153, pp. 65-78, 2000.
[47] R. Sun, D. Yang, L. Guo, and S. Dong, "Laser cladding of Ti-6Al-4V alloy with TiC and TiC+ NiCrBSi powders," Surface and Coatings Technology, vol. 135, pp. 307-312, 2001.
[48] J. Li, C. Chen, T. Squartini, and Q. He, "A study on wear resistance and microcrack of the Ti3Al/TiAl+ TiC ceramic layer deposited by laser cladding on Ti–6Al–4V alloy," Applied Surface Science, vol. 257, pp. 1550-1555, 2010.
[49] Q. Wu, J. Zhang, and Y. Sun, "Oxidation behavior of TiC particle-reinforced 304 stainless steel," Corrosion Science, vol. 52, pp. 1003-1010, 2010/03/01/ 2010.
[50] Y. Kitsunai, H. Kurishita, T. Kuwabara, M. Narui, M. Hasegawa, T. Takida, et al., "Radiation embrittlement behavior of fine-grained molybdenum alloy with 0.2wt%TiC addition," Journal of Nuclear Materials, vol. 346, pp. 233-243, 2005/11/15/ 2005.
[51] H. Kurishita, S. Kobayashi, K. Nakai, T. Ogawa, A. Hasegawa, K. Abe, et al., "Development of ultra-fine grained W–(0.25–0.8)wt%TiC and its superior resistance to neutron and 3MeV He-ion irradiations," Journal of Nuclear Materials, vol. 377, pp. 34-40, 2008/06/30/ 2008.
[52] Q. Fan, B. Li, and Y. Zhang, "The microstructure and properties of (FeCrNiCo) AlxCuy high-entropy alloys and their TiC-reinforced composites," Materials Science and Engineering: A, vol. 598, pp. 244-250, 2014.
[53] A. Takeuchi and A. Inoue, "Classification of bulk metallic glasses by atomic size difference, heat of mixing and period of constituent elements and its application to characterization of the main alloying element," Materials Transactions, vol. 46, pp. 2817-2829, 2005.
[54] G. Sheng and C. T. Liu, "Phase stability in high entropy alloys: formation of solid-solution phase or amorphous phase," Progress in Natural Science: Materials International, vol. 21, pp. 433-446, 2011.
[55] D. R. Askeland and W. J. Wright,"Essentials of materials science & engineering," Cengage Learning, 2013.