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电解含钛铝合金的疲劳性能研究
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摘要
电解低钛铝合金和电解铝硅钛合金是两种新型工艺生产的铝合金,对以二者和纯铝为基本原料制备的应用铸造合金的力学疲劳性能进行综合的对比研究,将会对客观评价这两种新材料的性能、在工业生产上推广新工艺,具有非常重要的现实意义和参考价值。
     文章首先考察了含钛铝合金当前在工业上的发展状况,以及我国在这方面与发达工业国家之间存在的差距,介绍了传统工艺方法生产含钛铝合金的局限性,以及两种新型工艺生产电解含钛铝合金的研究进展情况,强调了材料的疲劳性能在现代工程应用上的重要性。
     为研究铝合金中所含钛和电解加钛方式对铝合金疲劳性能的影响,分别利用电解低钛铝合金、电解铝硅钛合金和纯铝制备成三种铝硅系合金中重要的常用铸铝ZL101A和ZL101,测试其疲劳性能以及相关力学性能,并进行对比研究。微观组织分析结果表明,相对于不含钛的ZL101,微量的钛可以使电解低钛铝合金制备的ZL101A(AlTi101A)和电解铝硅钛合金制备的ZL101A(AST101A)的α(Al)相的晶粒细化,晶粒大小分布均匀,但对它们的Si粒子尺寸和形貌影响不大。
     以上述三种试验铝合金为对象,首先对比研究了不同的成分和组织对合金拉伸性能和断裂韧性的影响。结果表明,Ti对晶粒的细化可以大幅提高试验合金的抗拉强度、延伸率和断裂韧性,但对合金的屈服强度影响不大。AST101A中微量的Fe元素对合金的弹性模量会有所影响,对合金的抗拉强度和屈服强度影响很小,但会大大降低合金韧性和塑性。
     通过高周疲劳测试方法研究了AST101A和AlTi101A抵抗疲劳裂纹萌生的性能,把最大似然法和相关系数法结合起来处理不完全疲劳寿命数据,给出了AST101A的S—N曲线、P—S—N曲线和疲劳极限,讨论了加载历史、缺陷等对疲劳寿命的影响。
     对比研究了上述三种合金的化学成分对微观组织结构,及其所引起的材料疲
    
    郑州大学硕士论文
    电解含钦铝合金的疲劳性能研究
    劳裂纹扩展性能和疲劳门槛值的显著差异。结果表明,AST101A、AITi101A和
    ZL101中51粒子的浓度、大小和形貌对材料疲劳门槛值的高低有一定的作用,
    脆性的富Fe相是疲劳门槛值降低的另一个重要原因。随着疲劳裂纹扩展速率从
    近门槛值区向Paris区过渡,细小的a(A1)晶粒会加速疲劳裂纹的扩展。三种
    试验合金在Paris区的扩展没有明显的差别,表现出裂纹扩展速率在Paris区时,
    疲劳裂纹扩展对微观组织结构的不敏感性。但随后的扩展会受富Fe相和si粒子
    的大小和形貌的共同影响,致使ASTIOIA的扩展速率最大,而AITi101A的最小。
     本文较全面地测试和对比研究了以电解低钦铝合金和电解铝硅钦合金这两
    种新型电解含钦铝合金为原料制备的铸造合金ASTIOIA和AITi1OIA的疲劳性能
    以及相关力学性能。结果表明,电解低钦铝合金制备的AITi IOIA具有良好的拉
    伸性能、断裂韧性和抵制裂纹扩展的能力,电解铝硅钦合金中较高含量的Fe降
    低了AST 1 01A的疲劳性能以及相关的力学性能指标,因此降低电解铝硅钦合金中
    的铁含量,或使合金中的铁变质将会提高AST101A的疲劳性能和相关力学性能。
Electrolytic low content titanium aluminum alloy and electrolytic Al-Si-Ti alloy are two new alloy materials produced by new technique of production. It'll have very important practical value and referential significance in evaluating the properties of the two new materials and generalizing the new technique of production in industry to study and compare the fatigue properties and relevant mechanical properties of the applied cast alloys made from them and pure aluminum comprehensively.
    In this paper, current development of the titanium-contained aluminum alloys in industry and the gap between our country and advanced industrial counties were introduced first. The shortage of traditional technique for producing the titanium-contained aluminum alloy and the current research of the two new titanium-contained aluminum alloys produced in new technique were analyzed in detail. Then the significance of material's fatigue property in current engineering application was emphasized particularly.
    In order to study the influence of the existence and adding ways of trace titanium on the fatigue properties of aluminum alloys, three important common-used standard cast alloys ZL101A and ZL101 were prepared with electrolytic low content titanium aluminum alloy, electrolytic Al-Si-Ti alloy and pure aluminum respectively. The fatigue properties and relevant mechanical properties of these three cast alloys were tested and compared comprehensively. The analyses of their microstructure showed that comparing with ZL101 that contained no titanium, the trace amounts of titanium in alloys caused grain refining of Al-l%Si in ZL101A prepared from electrolytic low content titanium aluminum alloy (i.e. AlTi101A) and ZL101A prepared from electrolytic Al-Si-Ti alloy (i.e. AST101A), and the grain size distribution became more even, whereas the trace amounts of titanium have little influence on the size and
    
    
    
    shape of Si particles in these alloys.
    This paper studied the influence of different chemical components and microstructure in above aluminum alloys on their tensile properties and fracture toughness. The results showed that the grain refining by the trace amounts of titanium could improve the tensile stress, percentage elongation and fracture toughness, but had little influence on their yield stress. The trace amounts of iron hi AST101A could affect its elastic modulus, but not its tensile stress and yield stress, at the same time decrease its plasticity and fracture toughness notably.
    The abilities of resisting the incubation of fatigue crack in AST101A and AlTi101A were tested with the high-cycle fatigue method. A method combining the maximum likelihood estimation method with the correlation coefficient method was suggested to analyze the fatigue life experimental data some of which were incomplete. The S-N curve and P-S-N curves were presented, and the influence of the loading history and the defects in specimen on fatigue life was discussed.
    The remarkable differences of the fatigue crack propagating rates and the fatigue threshold among the above three alurninum alloys were studied and compared, which were caused by the microstructure based on alloys' chemical components. The results showed that the concentration, size and shape of Si particles in AlTilOlA, AST101A and ZL101 had some effects on the fatigue threshold, and the irregular shaped brittle phase of Fe intermetallics caused the fatigue threshold decreased. The fining grains of Al-l%Si could accelerate the fatigue crack propagation from the near threshold zone to Paris zone.
    The fatigue crack propagating rates of the above aluminum alloys in Paris zone had no remarkable differences. It was showed that fatigue crack propagating rates had little susceptivity to the microstructure of the above alloys in Paris zone. In contrast, the size and shape of Si particles and the phase of Fe intermetallics could affect the fatigue crack propagating rates beyond the Paris zone. The fatigue crack propagating rate of AST101A was the highest, and that of AlTilOlA was the lowest
引文
[1] 龚磊清,金长庚等.铸造合金金相图谱.湖南:中南工业出版社.1987.1~3.
    [2] 上海交通大学主编.铸造有色合金及其熔炼.北京:国防工业出版社,1980.
    [3] 杨冠群,杨升,杨巧芳,晏唯真,张伦和,顾青松.电解法生产铝硅钛多元合金述评.铸造,1999,4:51~54.
    [4] P.S. Mohnanty, J.E. Gruzleski Grain Refinement Mechanism of Hypoeuntectic Al-SiAlloys. Acta Mater, 1996,44:3749~3760.
    [5] 陆文华,李隆盛,黄良余.铸造合金及其熔炼.北京:机械工业出版社,1997.
    [6] M.M. Guzowski, G.K. Sigworth. Metall Trans, 1987, 18A:603~605.
    [7] P.S. Mohanty, J.E. Gruzleski, Mechanism of Grain Refinement in Aluminum. Acta Metall Mater, 1995,43:2001~2012.
    [8] J. Kaneko, M. Sangamata, R. Shimamune. Jpn Foundry Soc Trans, 1991,10:72~75.
    [9] L. Backernd, P. Gastafson, M. Johnson. Aluminum,1991,67:910~914.
    [10] 高泽生.Al—Ti—C晶粒细化用中间合金的最新进展.轻金属加工技术,1998,26.5~11.
    [11] 李双寿,朱跃峰等.中间合金对A356.2合金细化的效果.特种铸造及有色金属,2000,1:23~25.
    [12] 张映新.Al—Ti和Al—Zr中间合金组织遗传性对铝合金铸造组织的影响.轻金属加工技术,1998,26:11~13.
    [13] 方旭升.铝钛硼稀土中间合金的研制与生产.特种铸造及有色金属,1996,2:18~19.
    [14] 朱云,谢旭红.稀土铝钛硼晶粒细化剂的生成及应用.轻金属加工技术.1999,27.19~2.
    [15] 王明星.电解低钛铝合金工业试验及其组织与性能的研究.[博士学位论文],2002.1.
    [16] 杨冠群,杨升.电解法直接生产铝硅钛多元合金可行性分析.铸造.1977,1:
    
    44~46.
    [17] 杨留栓,杨涤心等.新型高钛活塞铝合金的研究.机械工程材料,1994,18:16~18.
    [18] 杨涤心.新型铝硅钛压铸合金的应用研究.热加工工艺,1999,2:44~45.
    [19] 鲁薇华,王汝耀等.电解Al—Si—Ti合金金相组织和性能.特种铸造及有色合金,1999,1:10~12.
    [20] 郑州大学,河南省登封铝业有限公司.电解法生产低钛铝基合金的技术与工艺研究的鉴定材料.2002.
    [21] 吕文阁.基于疲劳短裂纹行为的疲劳寿命估算.见:柳春图.疲劳与断裂.广州.2000年.北京:气象出版社.2002.95~97.
    [22] 储佳章,王建一.学科交叉融合,寿命定量设计.中国机械工程,1998,9:1~2.
    [23] 福克斯[美].工程中的金属疲劳.北京:中国农业机械出版社,1983.
    [24] 刘德刚,王凤洲,林春虎.国外疲劳研究及应用领域的新发展.铁道车辆,2001,9:10~12.
    [25] 华文林.现代疲劳技术在汽车测试中的应用.黄石高等专科学校学报,2002,18:49~50.
    [26] S.Suresh.材料的疲劳(第二版).王中光等译.北京:国防出版社.1999.
    [27] 高镇同,雄峻江.疲劳可靠性.北京:北京航空航天大学出版社.2000.
    [28] 郑修麟.机械加工对15MnVN钥等幅和变幅载荷下疲劳寿命的影响.见:柳春图.疲劳与断裂.广州.2000年.北京:气象出版社.2002.107~110.
    [29] J.T. Barnby, K. Dinsdal. Material Science & Engineering, 1976,26:245~250.
    [30] P.C. Paris , F. Erdogan .A critical analysis of crack propagation laws. Journal of Basic Engineering, 1963,85:528~534.
    [31] 张士林,任颂赞.简明铝合金手册.上海:上海科技出版社,2001.71~73.
    [32] Xiangfa Liu, Xiufang Bian and Jiaji Ma. A New Grain Refining Technique for Pure Al by Addition of Molten AlTiB Master Alloys. Materials science Forum, 2000, Vols. 331~337, 385~390.
    
    
    [33] 刘相法,边秀芳,周生存,黄保旭,马家骥.熔融AlTiB细化Al新工艺及形核机理.中国有色金属学报,1997,Vol.7,No.2,107~111.
    [34] 孝云祯,马宏声,路贵民,刘劲波,Al-Ti-B晶粒细化合金中的有效形核相,中国有色金属学报,1997,Vol.7.No.3,137~139.
    [35] 崔忠圻.金属学与热处理.北京:机械工业出版社,2003.56~58.
    [36] 铝合金用钛变质处理.陈学忠译.轻金属.1986,5:63~65.
    [37] 黄良余.铝及其合金的晶粒细化处理简述.特种铸造及有色金属.1997,3:41~43.
    [38] Liu Zhiyong, Wang Mingxing. Grain Refinement Effect and Mechanism of Al Based Alloy Containing Low-Content Ti Produced By Electrolysis. The Chinese Journal of Nonferrous Metals. 2002, Vol.
    [39] W.C. Winegard, B. Chomers. Trans ASM. 1954. Vol. 46, 1214.
    [40] Mark Easton, David Stjohn. Grain refinement of Aluminum alloys: Part I .The nucleate and solute paradigms-A review of the literature, Metallurgical and Materials Transactions A, 1999. Vol. 3OA, 6: 1613~1623.
    [41] 陆文华,李隆盛,黄良余.铸造合金及其熔炼.北京:机械工业出版社,2002.285~286.
    [42] 姜文辉,韩行霖,朱丽红.Al—12%Si合金α—Al晶粒细化剂的研究.铸造,1997,1:19~21.
    [43] C.E. Feltner, C. Laird. Cyclic stress-strain response of F.C.C. mentals and alloys-Ⅰ.Phenomenological experiments. Acta Metallurgica, 1967,15:1621~1632.
    [44] C.E. Feltner and C. Laird. Cyclic stress-strain response of F.C.C. mentals and alloys-Ⅱ.Phenomenological experiments. Acta Metallurgica,1967,15:1633~1653.
    [45] 匡震邦,顾海澄,李中华.材料的力学行为.北京:高等教育出版社,1998,5.
    [46] 戈康达·S[波兰].金属的疲劳与断裂.严名皋,刘才穆译.上海:上海科技
    
    出版社,1983.
    [47] 吕杰,刘波操,杨凯等.铸造铝铜合金的冲击韧性.材料科学与工程,1999,7:245~247.
    [48] 王从曾.材料性能学.北京:北京工业大学出版社,2001,6.
    [49] 王汝耀,鲁薇华.钛对AlSi7Mg0.3合金力学性能的影响.特种铸造及有色合金,1999,1:16~17.
    [50] 郑修麟.材料的力学性能.西安:西北工业大学出版社,1994:80~85.
    [51] 高镇同,蒋新桐等.疲劳性能试验设计和数据处理.北京:北经航空航天大学出版社,1999:15~17.
    [52] 熊峻江,高镇同.高置信度的典型任务实测载荷谱最少观测次数.机械强度,1996,1:18~20.
    [53] 傅惠民,高镇同.确定威布尔分布三参数的相关系数法.航空学报,1990,11(7):323~326.
    [54] 傅惠民,高镇同.a—N(a—t)曲线三参数幂函数拟合法.航空学报,1989,10(12):666~670.
    [55] 徐人平,傅惠民,高镇同.根据S—N曲线确定P—S—N曲线.机械强度,1994,16(1):58~60.
    [56] 佟晓君,马群.不完全寿命数据威布尔分布三参数估计法.唐山工程技术学院学报,1994,4:76~81.
    [57] N. Thompson, N.J. Wadsworth, N. Louat. The origin of fatigue fracture in copper. Philosophical Magazine, 1956,1:113~126.
    [58] W.A. Wood. Formation of fatigue cracks. Philosophical Magazine, 1958, 3:692~699.
    [59] A.J. Kennedy. Processes of Creep and Fatigue in Metals. New York: Wiley. 1963.
    [60] K. Gall, N. Yang, etc. The influence of modified intermetallics and Si particles on fatigue crack paths in a cast A356 Al alloy. Fatigue Fracture & Engineering Material structure, 2000,23: 159~172.
    [61] H.L. Ewalds, R.J.H. Wanhill. Fracture Mechanics. Chapman and Hall,
    
    New York,Ny,USA.
    [62] F.T.Lee,J.F.Major,F.H.Samuel.Effect of silicon particles on the fatigue crack growth characteristics of Al-12Wt Pct Si-0. 35 Wt Pct Mg-(0-0. 02) Wt Pct Sr casting alloys.Metall.Mater.Trans.,1995,26A:1553-1570.
    [63] M.Schaefer ,R .A.Fournelle.Effect of Strontium modification on near-threshold fatigue crack growth in an Al-Si-Cu die cast alloy.Metall.Mater.Trans.,1996,27A: 1293~1302.
    [64] A.Plumtree,S.Schafer.Initiation and short crack behavior in aluminum alloy casting.In:K.J.Miller,E.R.de los Rios ed..The Mechanical behavior of short fatigue cracks.EGF Publication 1:sufflok,UK,215-227.
    [65] G.A.Hoskin,J.W.Provan and J.E.Gruzleski,The In-situ Fatigue Testing of a Cast Aluminium-Silicon Alloy,Theoretical and Applied Fracture Mechanics,1988,Vol.10,27-41.
    [66] S.S.Xie,X.F.Pan,T.L.Wang,Effects of Microstructure on Fatigue Crack Growth Behavior in Ni-Base Superalloy GH586,ACTA Metallurgical Sinica (English Letters),1999,Vol.12,No.3,267-272.
    [67] S.Murali,A.Trivedi,K.S.Shamanna,K.S.S.Murthy.Effect of iron and combined iron and beryllium additions on the fracture toughness and microstructure of Squeeze cast Al-7Si-0. 3Mg alloy.F.mater.Engng Perform,1996,5:462-468.

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