摘要
功能梯度材料是一种综合性能优异的先进材料,其性能沿梯度方向连续变化,因而适用于在厚度方向上对性能有不同需求的工程构件。此类材料性能的梯度变化是由其不同位置处的化学成分、微观组织不同造成的。目前用于制备功能梯度材料的方法主要有粉末冶金法、离心铸造法、热喷涂、浸渗法和电磁相分离法等。
本论文探索了喷射沉积技术在梯度复合材料中应用的可行性,采用课题组自行设计的喷射沉积装置成功地制备了6066Al/SiC_P梯度复合材料,并对其进行了微观组织分析和性能检测。结果表明:SiC颗粒增强相的质量分数在沉积坯中沿沉积方向从底部到顶部由0%逐渐增加到30%,从而证实了喷射沉积法制备梯度复合材料的可行性。
论文开展了梯度复合材料沉积坯热致密化工艺的研究,提出了利用阶梯式压头对坯料进行致密化的新工艺,通过实验摸索出了适合于6066Al/SiC_P梯度复合材料致密化的工艺参数。结果表明:在压制温度为580℃、压制压力为220MPa、保压时间为10min的工艺参数下,采用阶梯式压头进行热模压致密化,可以将沉积坯的相对密度提高到99%以上。阶梯式压头热模压工艺可以有效地消除沉积坯中的孔隙,改善基体与增强颗粒间的界面结合情况,提高材料的致密度,特别适用于在较小的压制压力下对较大尺寸的坯料进行热模压致密化。经热致密化后,复合材料中SiC增强颗粒的浓度依然呈梯度分布。梯度复合材料的力学性能沿梯度方向呈现变化,在SiC颗粒浓度为15mass%时力学性能最高,达到428MPa。论文对比了致密化前后材料组织性能的变化并对其进行了分析讨论。初步探讨了阶梯式压头在热模压致密化过程中的机理,就坯料在致密化过程中的受力状态进行了分析讨论,指出了阶梯式压头致密化的优势,为进一步的研究打下了基础。
采用喷射沉积法制备SiC颗粒增强铝基梯度复合材料的工作尚未有类似报道。与其他方法相比,采用喷射沉积法制备的梯度复合材料具有组织细小、SiC增强颗粒在高度方向上呈连续梯度分布且可控性强,特别适合于制备大尺寸的梯度复合材料坯件。
Functionally gradient materials (FGMs), a new class of advanced and innovative materials which are capable of providing superior and reliable performance, are actively being sought for engineering devices that are subjected to two distinct service conditions on two opposite sides across the thickness direction. In a functionally graded material the properties change gradually with position. The property gradient in the material is caused by a position-dependent chemical composition, microstructure or phase composition. The processing techniques developed for preparing FGMs include powder metallurgy, centrifugal casting, thermal spraying, infiltration processing, electromagnetic separation, etc.
This thesis explored the feasibility of spray deposition in preparing functionally graded composites. The 6066Al/SiC_P graded composites were successfully prepared via the spray deposition system. This system was developed by our research team. The microstructure and mechanical properties of the preform were characterized. The results revealed that the SiC_P weight fraction of the as-deposited preform from the top to the bottom ranges almost continuously from 0 to 30%. This result indicated that spray deposition is a reliable approach in producing the FGMs.
Densification was conducted on the spray deposited graded composites in this thesis. A novel technique named as stepped force plug pressing was developed. The optimized processing parameter appropriated for 6066Al/SiC_P was obtained through experiments. The results showed that the relative density of the composites was above 99% after densification with the stepped force plug pressing in the processing parameter of 580℃, 220MPa and 10min pressure retaining. The stepped force plug pressing showed excellent perfermence in eliminating the porosity in the preform and improve the interface between the matrix and the reinforcement particles. It is applicable to densify larger preform with less pressure. The SiC particles in the preform still presented a graded feature after densification. The tensile strength of the graded composite varied with different SiC percentage and achieved a peak value 428MPa at 15mass% SiC weight percentage. The results and discussions were given about the different structures and properties between the spray deposited preform and densified composites. The mechanism of the stepped force plug pressing and the stress of the preform during the densification were simply analyzed. The advantages of this novel densification technique were presented, which laid a foundation for its further development.
There was no similar report in researchs about SiC_P reinforced aluminum matrix graded composites preparing via spray deposition. Compared with graded composites preparing by other techniques, spray deposited graded composites have advantages of fine grain and easy in controlling. Spray deposition was especially suitable in preparing large graded composites.
引文
[1] Kieback B, Neubrand A, Riedel H. Processing techniques for functionally graded materials. Materials Science and Engineering A, 2003, 362(1-2):81-106
[2]许富民,齐民,李守新,等. SiC颗粒增强铝基梯度复合材料的制备与性能.金属学报, 2002, 38(9):998-1001
[3]袁秦鲁,胡锐,李金山,等.梯度复合材料制备技术研究进展.兵器材料科学与工程, 2003, 26(6):66-69
[4] Amada S, Munekata T, Nagase Y, et al. The mechanical structures of bamboos in viewpoint of functionally gradient and composite materials. Composite Materials, 1996, 30(7):800-819
[5]许富民.梯度分布的SiC颗粒增强铝基复合材料的制备,组织和力学行为: [博士学位论文].大连:大连理工大学材料科学与工程学院, 2004
[6] Guo J, Yuan X. The aging behavior of SiC/Gr/6013Al composite in T4 and T6 treatments. Materials Science and Engineering: A, 2009, 499(1-2):212-214
[7] Mahadevan K, Raghukandan K, Senthilvelan T, et al. Studies on the effect of delayed aging on the mechanical behaviour of AA 6061 SiCp composite. Materials Science and Engineering A, 2005, 396(1-2):188-193
[8] Gómez de Salazar J M, Barrena M I. Influence of heat treatments on the wear behaviour of an AA6092/SiC25p composite. Wear, 2004, 256(3-4):286-293
[9] Mondal D P, Das S, Suresh K S, et al. Compressive deformation behaviour of coarse SiC particle reinforced composite: Effect of age-hardening and SiC content. Materials Science and Engineering: A, 2007, 460-461:550-560
[10] Hu M, Fei W D, Yao C K. Effect of heat treatment on dislocation states and work hardening behaviors of SiCw/6061Al composite. Materials Letters, 2002, 56(5):637-641
[11] Rajan T P D, Pillai R M, Pai B C. Reinforcement coatings and interfaces in aluminium metal matrix composites. Journal of materials Science, 1998, 33(14):3491-3503
[12] Cheng N P, Li C M, Hui Q, et al. Effect of particle surface treatment on the microstructure and property of SiCp/AA6066 composite produced by powder metallurgy. Materials Science and Engineering: A, 2009, 517(1-2):249-256
[13] Lee J-C, Byun J-Y, Oh C-S, et al. Effect of various processing methods on theinterfacial reactions in SiCp/2024 Al composites. Acta Materialia, 1997, 45(12):5303-5315
[14]新野正之,平井敏雄,渡边龙三.倾斜机能材料.日本复合材料学会志, 1987, 13:257-264
[15]邢世凯.梯度功能材料及其在内燃机上的应用研究.汽车工艺与材料, 2004, 16(10):6-8
[16]李耀天.梯度功能材料的研究与应用.金属功能材料, 2000, 7(4):15-23
[17]解念锁.梯度功能材料的制造方法及应用.陕西工学院学报, 2002, 18(2):4-7
[18] Nai S M L, Gupta M. Synthesis and characterization of free standing, bulk Al/SiCp functionally gradient materials: effects of different stirrer geometries. Materials Research Bulletin, 2003, 38(11-12):1573-1589
[19]郭成,易树清,胡晓东,等. SiC颗粒增强铝合金基梯度复合材料的制备及其组织和性能.中国有色金属学报, 1998, 8(A01):123-127
[20]袁秦鲁. SiCp/Al复合材料及其梯度复合材料的制备与性能研究: [硕士学位论文].西安:西安理工大学材料科学与工程学院, 2004
[21]徐永东,柴东朗.层状梯度结构SiC颗粒增强铝基复合材料的损伤分析.兵器材料科学与工程, 2000, 23(3):20-22
[22] Lin C Y, McShane H B, Rawlings R D. Structure and properties of functionally gradient aluminium alloy 2124/SiC composites. Materials Science and Technology, 1994, 10(7):659-664
[23] Brinkman H J, Duszczyk J, Katgerman L. In-situ formation of TiB2 in a P/M aluminum matrix. Scripta Materialia, 1997, 37(3):293-297
[24]李健,陈体军,郝远,等.离心铸造法制备Al3Ti/Al原位自生功能梯度复合材料.热加工工艺, 2007, 36(5):31-34
[25]秦孝华,韩维新,范存淦,等.离心铸造法制备陶瓷颗粒增强Al合金基功能梯度复合管.金属学报, 2001, 37(10):1117-1120
[26]张新平,于思荣,何镇明.离心加速场中金属凝固过程温度场分布数值分析.复合材料学报, 2001, 18(2):75-80
[27]徐自立,林汉同.离心铸造铝基自生梯度复合材料的热物性能.特种铸造及有色合金, 2001, 22(4):16-18
[28]杜卓林,陈义良,黄庆,等.离心力作用下Al/SiCP系统二维凝固过程的数值模拟.金属学报, 2002, 38(4):359-364
[29]费劲,张卫文,陈维平,等.半连续铸造制备2024/3003梯度材料的研究.特种铸造及有色合金, 2003, 24(1):24-26
[30] Rodríguez-Castro R, Wetherhold R C, Kelestemur M H. Microstructure andmechanical behavior of functionally graded Al A359/SiCp composite. Materials Science and Engineering A, 2002, 323(1-2):445-456
[31] Qin X H, Han W X, Fan C G, et al. Research on distribution of SiC particles in aluminum-alloy matrix functionally graded composite tube manufactured by centrifugal casting. Journal of Materials Science Letters, 2002, 21(8):665-667
[32] Watanabe Y, Oike S. Formation mechanism of graded composition in Al-Al2Cu functionally graded materials fabricated by a centrifugal in situ method. Acta Materialia, 2005, 53(6):1631-1641
[33] Lai W, Munir Z A, McCoy B J, et al. Centrifugally-assisted combustion synthesis of functionally-graded materials. Scripta Materialia, 1997, 36(3):331-334
[34] Duque N B, Melgarejo Z H, Suárez O M. Functionally graded aluminum matrix composites produced by centrifugal casting. Materials Characterization, 2005, 55(2):167-171
[35] Mizuno M, Abe K I, Inoue T. Processing of metal matrix composite by centrifugal casting technique and evaluation of the elastic properties. Zairyo, 1997, 46(8):946-951
[36] Gomes J R, Rocha L A, Crnkovic S J, et al. Friction and Wear Properties of Functionally Graded Aluminum Matrix Composites. Materials Science Forum, 2003, 423-425:91-96
[37] Yamanaka N, Watanabe Y, Fukui Y, et al. Manufacturing process of shirasu/aluminum FGM and its thermal conductivity. Japan Institute of Light Metals, 1994, 44(6):330-335
[38] Sequeira P D, Watanabe Y, Fukui Y. Backward extrusion of Al-Al3Ti functionally graded material: Volume fraction gradient and anisotropic orientation of Al3Ti platelets. Scripta Materialia, 2005, 53(6):687-692
[39] Yamagiwa K, Watanabe Y, Fukui Y, et al. Novel recycling system of aluminum and iron wastes-in-situ Al-Al3Fe functionally graded material manufactured by a centrifugal method: New systems and processes in recycling and high performance waste treatments. Materials transactions-JIM, 2003, 44(12):2461-2467
[40] Velhinho A, Sequeira P D, Martins R, et al. X-ray tomographic imaging of Al/SiCp functionally graded composites fabricated by centrifugal casting. Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms, 2003, 200:295-302
[41] Kyung M C, II D C, IK M P. Thermal Properties and Fracture Behavior of Compositionally Graded Al-SiCp Composites. Materials Science Forum, 2004, 449-452:621-624
[42]王扬卫,王富耻,李俊涛,等.无压浸渗制备梯度Si3N4/Al复合材料.功能材料, 2004, 35(z1)
[43]崔岩,张少卿. SiC颗粒粒度对熔铝氧化渗透合成SiCP/Al2O3-Al复合材料微观断裂机制的影响.材料工程, 2000, 45(6):3-6
[44]朱秀荣,童文俊.陶瓷纤维增强铝基复合材料研究.宇航材料工艺, 2000, 30(3):42-44
[45]武高辉,赵永春.亚微米级Al2O3颗粒增强LD2铝合金复合材料的拉伸性能与强化机制.复合材料学报, 1998, 15(3):21-26
[46]刘小梅,刘静.短纤维增强铝硅合金梯度复合材料耐磨性能的研究.江西理工大学学报, 2007, 28(3):14-17
[47]王荣,朱秀荣,费良军,等.梯度复合材料活塞的挤压铸造研究.特种铸造及有色合金, 2001, S1:135-136
[48]陈东风,曹志强,杨淼,等.高频磁场下制备表面增强自生梯度复合材料.铸造, 2006, 55(8):821-824
[49] Takahashi K, Taniguchi S. Fabrication of aluminum-matrix composites locally reinforced with SiC particles by using electromagnetic force. Keikinzoku, 2005, 55(10):483-488
[50]刘红才,曹志强,张红亮,等.高频磁场下制备Al-Mg2Si-Al2O3梯度复合材料.功能材料, 2008, 39(2):216-219
[51] Gupta M, Lai M O, Srivatsan T S. Synthesis and Characterization of a Free-Standing, One-Dimensional, Al-Cu/SiC-Based Functionally Graded Material. Journal of Materials Synthesis and Processing, 2002, 10(2):75-81
[52] Pinto P, Mazare L, Soares D, et al. Incremental Melting and Solidification Process/Mechanical Characterization of Functionally Graded Al-Si Alloys. Materials Science Forum, 2008, 587-588:400-404
[53] Scanlan M, Browne D J, Bates A. New casting route to novel functionally gradient light alloys. Materials Science and Engineering: A, 2005, 413-414:66-71
[54] Guntner A, Sahm P R. Graded Metal Matrix Composites Produced by a Multi-Pouring Method with Controlled Mold Filling. Materials Science Forum, 1999, 308-311:187-192
[55] Yang C C. Method for making graded composite bodies and bodies producedthereby. United States Patent. 5549151, 1996-08-27
[56] Singer A R E. Recent Developments in the Spray Forming of Metals. International Journal of Powder Metallurgy and Powder Technology, 1985, 21(7):219-222
[57]袁武华.喷射沉积轻量化材料的研制——高性能7075/SiCP复合材料、8009合金板材的制备及应用研究: [博士后学位论文].长沙:湖南大学材料科学与工程学院, 2005
[58]康智涛.大尺寸多层喷射沉积6066Al/SiCp/Cr复合材料管坯的制备: [博士学位论文].长沙:中南大学材料科学与工程学院, 2001
[59] Gupta M, Mohamed F A, Lavernia E J. The Effect of Ceramic Reinforcements during Spray Atomization and Codeposition of Metal Matrix Composites. Metallurgical Transactions A, 1992, 23(3):831-850
[60]张福全.大尺寸7075/SiCP复合材料的喷射共沉积制备技术及后续加工问题研究: [博士学位论文].长沙:湖南大学材料科学与工程学院, 2005
[61] Baskin D, Wolfenstine J, Lavernia E J. Elevated Temperature Mechanical Behavior of CoSi and Particulate Reinforced CoSi Produced by Spray Atomization and Co-deposition. Journal of Materials Research, 1994, 9(2):362-371
[62] Gupta M, Juarez-Islas J, Frazier W E, et al. Microstructure, Excess Solid Solubility and Elevated-Temperature Mechanical Behavior of Spray-Atomized and Co-Diposited Al-Ti-SiCP. Metallurgical Transactions B, 1992, 23(6):719-736
[63] Perez R J, Zhang J, Gungor M N, et al. Damping Behavior of 6061Al/Cr Metal Matrix Composites. Metallurgical Transactions A, 1993, 24(3):701-712
[64]柏振海,黎文献,王日初.喷射沉积SiCP/Al复合材料及6066铝合金热挤压工艺的研究.铝加工, 2003, 150(3):27-30
[65]熊柏青,朱宝宏,张永安,等.喷射成形Al-Fe-V-Si系耐热铝合金的制备工艺和性能.中国有色金属学报, 2002, 12(2):250-254
[66]陈飞凤.喷射沉积坯料外框限制轧制工艺及变形规律研究: [硕士学位论文].长沙:湖南大学材料科学与工程学院, 2007
[67]龚艳丽.喷射沉积多孔材料陶粒轧制工艺的研究: [硕士学位论文].长沙:湖南大学材料科学与工程学院, 2007
[68] Park J J. Constitutive relations to predict plastic deformations of porous metals in compaction. International Journal of Mechanical Sciences, 1995, 37(7):709-719
[69]詹美艳.喷射沉积材料压缩和轧制变形规律研究: [博士学位论文].长沙:湖南大学材料科学与工程学院, 2005
[70]宋旼,肖代红.锻造对Al-Fe-V-Si合金力学性能与显微组织的影响.稀有金属材料与工程, 2007, 36(A03):208-210
[71]肖于德,谭敦强,黎文献,等.快速凝固AlFeX耐热铝合金喷射沉积坯锻造成型工艺试验研究.材料科学与工艺, 2006, 14(5):519-523
[72]孙有平,严红革,陈振华,等.楔压加工对SiCP/7090铝基复合材料的影响.特种铸造及有色合金, 2008, 28(1):1-3
[73]肖于德,吴永玉,黎文献,等.旋压加工对喷射沉积Al-8.5Fe-1.3V-1.7Si合金挤压管组织和性能的影响.中南大学学报, 2005, 36(3):358-363
[74]柏振海. 6066Al/SiCP复合材料弹性模量、内耗及加工制备的研究: [博士学位论文].长沙:中南大学材料科学与工程学院, 2006
[75] Rajan T P D, Pillai R M, Pai B C. Reinforcement coatings and interfaces in aluminium metal matrix composites. Journal of materials Science, 1998, 33(14):3491-3503
[76] Lee J-C, Byun J-Y, Oh C-S, et al. Effect of various processing methods on the interfacial reactions in SiCp/2024 Al composites. Acta Materialia, 1997, 45(12):5303-5315
[77] Lee J-C, Ahn J-P, Shim J-H, et al. Control of the interface in SiC/Al composites. Scripta Materialia, 1999, 41(8):895-900
[78] Thanh L N, Suéry M. Influence of oxide coating on chemical stability of SiC particles in liquid aluminium. Scripta Metallurgica et Materialia, 1991, 25(12):2781-2786
[79] Zhong W M, Esperance G L, Suery M. Interfacial Reactions in Al-Mg (5083)/SiCp Composites during Fabrication and Remelting. Metallurgical and Materials Transactions A, 1994, 26(10):2637-2649
[80] Gupta M, Mohamed F A, Lavernia E J. Solidfication behavior of Al-Li-SiCp MMCs processed using variable codeposion of multi-phase. Materials Manufacture Processes, 1990, 4(5):165-170
[81]傅定发,康智涛,陈振华.喷射沉积过程的理论模型.材料导报, 2000, 14(6):16-18
[82] Gupta M, Loke C Y. Synthesis of free standing, one dimensional, Al---SiC based functionally gradient materials using gradient slurry disintegration and deposition. Materials Science and Engineering A, 2000, 276(1-2):210-217
[83]李云平,李溪滨. SiCP颗粒增强耐热铝基复合材料孔隙率与力学性能.中南工业大学学报, 2002, 33(2):177-180
[84] Emamy M, Razaghian A, Kaboli S, et al. Statistical analysis of tensile properties of cast A357/Al2O3 MMCs. Materials Science and Technology, 2010, 26(2):149-156
[85]范才河.喷射沉积5A06铝合金楔压致密化工艺的研究: [硕士学位论文].长沙:湖南大学材料科学与工程学院, 2006
[86]王凯.梯温楔压对喷射沉积SiCP/7090铝基复合材料致密化的影响: [硕士学位论文].长沙:湖南大学材料科学与工程学院, 2008
[87]刘鹏飞.大尺寸喷射沉积Al-20%Si/SiCP环件楔压致密化工艺的研究: [硕士学位论文].长沙:湖南大学材料科学与工程学院, 2006
[88]杨寿智.喷射沉积7075/SiCP复合材料压缩变形规律和锻造工艺研究: [硕士学位论文].长沙:湖南大学材料科学与工程学院, 2005
[89] Fernández P, Bruno G, González-Doncel G. Macro and micro-residual stress distribution in 6061 Al-15 vol.% SiCw under different heat treatment conditions. Composites Science and Technology, 2006, 66(11-12):1738-1748
[90] Mahadevan K, Raghukandan K, Senthilvelan T, et al. Investigation on the influence of heat-treatment parameters on the hardness of AA6061-SiCp composite. Journal of Materials Processing Technology, 2006, 171(2):314-318
[91]孙有平.塑性成形对喷射沉积7090Al/SiCP复合材料SiC分布及组织性能影响: [博士学位论文].长沙:湖南大学材料科学与工程学院, 2009
[92] Xu Q, Hayes R W, Hunt W H, et al. Mechanical properties and fracture behavior of layered 6061/SiCp composites produced by spray atomization and co-deposition. Acta Materialia, 1998, 47(1):43-53
[93]陈振华,张豪.多层喷射共沉积法制备6066铝合金/SiC颗粒复合材料.中国有色金属学报, 1996, 6(4):83-86
[94] Radmilovic V, Thomas G, Das S K. Microstructure ofα-Al base matrix and SiC particulate composites. Materials Science and Engineering: A, 1991, 132:171-179
[95]何梅琼. SiC颗粒强化铝基复合材料及其断裂韧性.铝加工, 1998, 21(2):55-58
[96]宋旼,李侠,陈康华.颗粒增强铝基复合材料断裂韧性与拉伸延性的解析模型.材料科学与工程学报, 2007, 25(5):690-694
[97]覃继宁,张荻,张国定,等.颗粒增强金属基复合材料的断裂韧性有限元分析.复合材料的现状与发展, 2000, 754-758