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镁合金凝固组织的超声细化机制及工艺研究
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摘要
镁合金具有密度小、比强度高、阻尼性能好及电磁屏蔽等优点,在汽车、电子、通讯等工业领域得到了日益广泛的应用。但是在镁合金的广泛应用中,改善其塑性变形能力仍然是一个非常关键的问题。
     实践证明,细小等轴晶的组织能提高镁合金的机械性能。因此找到一种实用有效的工艺来细化镁合金的晶粒就显得非常重要。超声波处理作为一种高效、无污染的物理细晶技术,能显著的细化金属的凝固组织。但是至今人们对于超声细化镁合金的研究比较少,因此有必要在该领域内展开深入的研究,并对超声细化镁合金凝固组织的作用机制及工艺参数进行探讨。
     本文在AZ31B和AZ91D镁合金的凝固过程中进行超声熔体处理,对超声细化镁合金凝固组织的机制及工艺进行了较为深入系统的研究。
     首先采用了超声物理模拟实验的方法,使用甘油、亚甲基蓝水溶液、NH_4Cl水溶液作为模拟介质进行超声处理,研究了声流、声空化、超声细化的影响因素。结果表明:超声功率、模拟介质温度、超声处理时间、变幅杆位置等影响了超声的声流范围;超声功率、超声处理时间、超声作用的距离等影响了超声空化的强度;超声功率、超声处理时间、NH_4Cl水溶液浓度等影响了NH_4Cl水溶液的结晶过程和晶粒尺寸。
     其次采用量热法对声功率进行了测定,计算出换能器的平均效率。为了进一步探讨功率超声细化镁合金的机理,本文测定了0W、200W、400W、600W、800W功率超声下AZ31B和AZ91D镁合金冷却曲线。研究结果表明,功率超声提高了凝固开始温度和凝固结束温度,缩短了凝固时间,凝固冷却速率加快。
     再次,在AZ31B和AZ91D镁合金凝固过程中研究了超声细化工艺参数(超声处理温度区间、超声功率、超声衰减、冷却方式)的影响。实验结果表明,超声连续处理、超声功率为600W、水冷时,对镁合金的细化效果最好。验证了功率超声在金属熔体中存在比较严重的衰减这一物理现象,即超声细化区域是有限的。
     最后,轧制性能试验证明了超声处理能显著提高AZ31B镁合金的塑性及轧制性能。
Magnesium alloys are increasingly applied into the automotive, electronics and communication industries due to their low density high, strength-to-weigh, rigidity-to-weigh ratio, good damping capacity and good electromagnetic shielding properties. However, the key problem to extend the wide application magnesium alloy is to improving deforming ability.
     Many practices proved that the fine equiaxed crystals structure magnesium alloys could improve mechanical properties. It is very important to find an effective grain refinement for magnesium alloys. Ultrasonic treatment is an efficient and non-contaminative metal refining technique. However, few research on the grain fining of magnesium alloys with ultrasonic in solidification process was done before. Therefore, it needs urgently to carry out a deep-going investigation in this region, which includes discussing the mechanisms of grain fining of magnesium alloys with ultrasonic and the technological parameter. In this paper, the solidification process of AZ31B and AZ91D magnesium alloys was processed by power ultrasonic, and the mechanism and technology of power ultrasonic refinement was widely investigated.
     Firstly, the method of ultrasound physical modeling experiments was used to study on effects of various factors, such as acoustic streaming, ultrasonic cavitation , on ultrasonic refinement process. And the glycerol, methylene blue solution and ammonium chloride are selected as physical simulation medium of ultrasonic treatment The experimental results show that the effective range of the acoustic stream is different while the ultrasonic power, the medium temperature, the ultrasonic treatment time and the location of ultrasonic amplitude amplifier pole are changed. And the intensity of ultrasonic cavitation is different with changing ultrasonic power, ultrasonic treatment time and distance of ultrasonic amplitude amplifier pole. Also the crystallization of ammonium chloride is different with changing ultrasonic power, ultrasonic treatment time and the concentration of ammonium chloride.
     Secondly, sound power was measured by calorimetry and efficiency of transducer was calculated. In order to probe into the solidification mechanism of AZ31B and AZ91D magnesium alloys when power ultrasonic was directed into the molten melt, the cooling curves of AZ31B and AZ91D magnesium alloys under 0W, 200W, 400W, 600W and 800W ultrasonic power were measured. The research results showed that the solidifying beginning and end temperature were improved. Furthermore, the solidification time become shorter and the cooling rate of solidification become faster.
     Thirdly, the effects of processing parameters such as the temperature range, ultrasonic power, attenuation and the cooling mode of ultrasonic treatment on ultrasonic refinement process were researched by introducing power ultrasonic into the solidification process of AZ31B and AZ91D magnesium alloys .The experimental results showed that with continuous treatment, 600w ultrasonic power and water-cooling mode, the finest refining effect on magnesium alloy could be achieved. The ultrasonic attenuation exists along the ultrasonic propagation in the molten metals .And the range of ultrasonic refinement was limited.
     Lastly, the rolling deforming tests prove that the deforming properties of AZ31B alloy after ultrasonic treatment was enhanced significantly.
引文
[1]刘子利,沈以赴,李子全,等.铸造镁合金的晶粒细化技术[J].材料科学与工程学报,2004,22(1):146-139.
    [2]甄子胜,毛卫民等.电磁搅拌工艺参数对半固态AZ91D镁合金组织的影响[J].北京科技大学学报.2003,25(4):341-345.
    [3]翟春生,许光明,崔建忠.镁合金电磁铸造中搅拌频率的确定[J].轻合金加工技术,2002,31(2):12-15.
    [4]张新建等.近液相线半连续铸造AZ91D镁合金微观组织研究[J].材料与冶金学报.2002,1(3):218-222.
    [5]袁晓光,刘正,许沂.电磁铸造对AZ91D合金组织及力学性能的影响[J].中国有色金属学报,2002,12(4):784-790.
    [6]张莹,耿茂鹏,谢水生等.镁合金的双辊板带连续铸轧技术[J].铸造技术.2005(1):79-81.
    [7]张莹,耿茂鹏,饶磊,谢水生.镁合金半固态双辊板带流变成形试验研究[J].热加工工艺.2005(10):10-12.
    [8]周尧和,胡壮麒,介万奇.凝固技术.北京:机械工业出版社,1998.
    [9]陈存中.有色金属熔炼与铸锭.北京:冶金出版社,1987。
    [10]张诗昌,段汉桥,蔡启舟等.镁合金的熔炼工艺现状及发展趋势[J].特种铸造及有色冶金,2000,(6):51-54.
    [11]陆文华,李隆盛,黄良余.铸造镁合金及其熔炼[M].北京:机械工业出版社,1996.
    [12]吕宜振,曾小勤,丁文江.镁合金铸造成形技术的发展[J].铸造.2000,49(7):383-387.
    [13]李远东,郝远,陈体军等.镁合金半固态成形的现状及发展前景[J].特种铸造及有色冶金.2001,(2):77-78.
    [14]杨明波,潘复生,李忠盛等.镁合金铸态晶粒细化技术的研究进展.[J].铸造,2005,54(4):314-318.
    [15]Lee Y C,Dahle A K,Sbjohn D H.The Role of solute in grain refinement of magnesium[J].Metallurgical and Materials Transaction,2000,31A:2895-2906.
    [16]Yosuke Tamura,Tadashi Haitani,Eiji Yano,et al.Grain refinement of highpurity Mg-Al alloy ingots and influences of minor amounts of iron and manganese on cast grain size[J].MaterialsTransactions,2002,43(11):2784-2788.
    [17]赵浩峰,刘红梅,张永忠,等.镁合金晶粒细化的研究[J]轻合金加工技术,2004,32(2):10-14.
    [18]张世军,黎文献,余琨,等.镁合金晶粒细化工艺[J].铸造,2001,50(7):373-375.
    [19]刘生发,范晓明,王仲范.钙在铸造镁合金中的作用[J]铸造,2003,52(4):246-248.
    [20]闵学刚,孙扬善,杜温文,等.Ca、Si和RE对AZ91合金的组织和性能的影响[J].东南大学学报(自然科学版),2002,32(3):1-6.
    [21]李培杰,郑伟超,汤彬,等.Ca和Sr对AZ91D合金组织的细化作用[J].特种铸造及有色合 金,2003,(3):8-10.
    [22]Aliravci A,Gruzleski J E.Effect of Strontium on the shrinkage microporosity in magnesium sand castings[J].AFS Transactions1992,(100):353-362.
    [23]Nussbau G m,Bribot P,Warner T J,et al.New Mg-Al based alloys with improved casting and corrosion properties[J]Mordike B L,Hehmann.Magnesium Alloys and Their Application(C),Oberursed Germany,1992:351-358.
    [24]许光明,包卫平,崔建忠,等.不同磁场作用下ZK60镁合金的凝固组织[J].东北大学学报(自然科学版),2004,25(1):48-50.
    [25]包卫平,许光明,崔建忠.均恒磁场作用下AZ61镁合金的凝固组织[J].轻合金加工技术,2003,31(12):6-9.
    [26]白晓清.超声波作用下液体中夹杂物迁移行为:(博士学位论文).沈阳:东北大学,2002.
    [27]冯若.超声手册.南京:南京大学出版社,1999.
    [28]金长善.超声工程.哈尔滨:哈尔滨工业大学出版社,1989:1-3.
    [29]应崇福.超声学.北京:科学出版社,1990.
    [30]冯若,李化茂.声化学及其应用[M].合肥:安徽科学技术出版社,1992.
    [31]高守雷.功率超声对金属凝固组织的影响:(硕士学位论文).上海:上海大学,2003.
    [32]冯伟骏.功率超声对Pb-Sn合金凝固行为的影响:(硕士学位论文).大连:大连理工大学,2004.
    [33]G.I.Eskin.Broad prospects for commercial application of the ultrasonic(cavitation)melt treatment of light alloys.Ultrasonics Sonochemistry,2001,8:319-325.
    [34]常国威,王建中.金属凝固过程中的晶体生长与控制[J].北京:冶金工业出版社,20028(11):A605-612
    [35]Witzke S,Riquet J P,Durand F.Diffusion Field Ahead of a Growing Columnar Front:Discussion of the Columnar-equiaxed Transition[J].Acta Metallurgica.1981,29:365-374.
    [36]Lipton J,Kurz W,Heinemann W.Modeling Columnar to Equiaxed Transition[M].Contenst Technol.News。1983,22:4-6.
    [37]陈峰。振动作用下铝合金的凝固、组织与性能特点。东南大学博士学位论文,1990
    [38]马立群,舒光冀,陈锋.金属熔体在超声场中凝固的研究[J].材料科学与工程,1995,13(4):2-7.
    [39]张海波.功率超声对AZ81镁合金凝固组织的影响:(硕士学位论文).上海:上海大学,2004.
    [40]Eskin G I.Ultrasonic Treatment of Molten Aluminum[J].Metallurgiya,Moscow:1985.
    [41]Abramov O V.Gurevich Ya B.Material,r,1974,(1):44-48.
    [42]Dobatkin V I,Eskin G I.The Efect of High Intensity Ultrasound on the Phase Interface in Metals.Naulka.Moscow:1986,87-93.
    [43]Eskin G I,Ultrasonic Treatment of Melts in Shape Casting and Continuous Casting of LightAlloys.Mashinostroenie,Moscow,1975.
    [44]DobatkinV I,Eskin G I.The Efect of High-intensity Ultrasound on the Phase Interface in Metals.Nauka,Moscow,1986.
    [45]李英龙,李宝绵,刘永涛,等.功率超声对Al-Si合金组织和性能的影响[J].中国有色金属学 报.1999,9(4):719-722.
    [46]赵忠兴.超声波对合金结晶过程的均匀化作用[J].热加工工艺.1999.5:10-11.
    [47]戚飞鹏,高守雷,侯旭等.超声功率对锡锑合金凝固组织的影响[J].上海大学学报.2003,9(1):42-46
    [48]高守雷,翟启杰,戚飞鹏等.超声波在金属凝固中的应用与发展[J].材料导报2002,[9]:9月16卷.
    [49]高守雷,张家涛,李祖齐,戚飞鹏等.超声场下熔体温度对SnSb合金凝固组织的影响[J].特种铸造及有色合金..2003,[3]21-23
    [50]李军文,桃野正.超声波导入杆与振动子之间的共振度对铝合金铸定组织的影响及其模拟试验[J].轻合金加工技术.2004,[5]:6-32..
    [51]李军文,桃野正.超声波对分配系数K>1的铝合金铸锭组织的影响[J].轻合金加工技术2004,[4]:9-32.
    [52]李军文,桃野正.超声波开始导入时的熔体温度对Al-Cu合金铸锭组织的影响[J].轻合金加工技术.2004,[4]:248-250.
    [53]胡化文,陈康华,刘红卫,黄兰萍,朱武,郑强.熔体超声处理对7055铝合金显微组织和性能的影响[J].粉末冶金材料与科学.2004,[2]:9卷:156-159.
    [54]陈锋,舒光冀,马立群,等.高能超声作用下数种金属基复合材料的制备及机制[J].复合材料学报,1998,15(3):12-16.
    [55]Campbell J.Effects of Vibration during solidification.Int Met Rev,1981,(2):71-104
    [56]赵忠兴,毕鉴智,郑一,等.铝合金超声铸造技术[J].特种铸造及有色合金,1999(1):13-14.
    [57]SanchezC,LivageJ,Henry M,et al.Chemical modification of alkoxide precursors.[J]Non-cryst.Solids 1988,100:65-76.
    [58]肖立隆.铝及铝合金超声波冶金的设计与物理基础(三).铝加工技术.1989(3):19-29.
    [59]程存弟.功率超声.超声技术及其应用[M].西安:陕西师范大学出版社.1993.
    [60]林书玉.功率超声技术的研究现状及其最新进展[J].陕西师范大学学报(自然科学版),2001,29(1):101-106.
    [61]林书玉.超声换能器的原理及设计[M].北京:科技出版社,2004.
    [62]林仲茂.声化学研究概况[J].应用声学,1993,12(1):1-5.
    [63]沈忠厚.水射流理论与技术[M].山东东营:石油大学出版社,1998,31.
    [64]张林夫,夏维洪.空化与空蚀[M].南京:河海大学出版社,1989,111.
    [65]冯若.超声空化与超声治疗.自然杂志,2003,25(6):311-314.
    [66]林仲茂.20世纪功率超声在国内外的发展.声学技术,2000,19(2):101-105.
    [67]Lord Rayleigh.Philos.Mag.34(1917)94.
    [68]T.J.Mason and J.P.Lorimer,Sonochemistry:Theory,Applications and Uses of Ultrasound in Chemistry,Ellis Horwood Limited,1988.
    [69]F.Faid,F.Contamine,A.M.Wilhelm,et al,Comparison of ultrasound effects in Different reactors at 20kHz,Ultrasonics Sonochemistry,1998,5,119-124.
    [70]B.Pugin,Qualitative characterization of ultrasound reactors for heterogeneous Sonoehemistry, Ultrasonics,1987,25(1),49-55.
    [71]I.P.MarangoPoulos,C.J.Martin,J.M.S.Hutchison,Measurement of field distributions in ultrasonic cleaning baths:ImPlications for cleaning efficiency.Physics in Medicine and Biology,1995,40(11),1897-1908.
    [72]J.L.Laborde,A.Hita,J.P.Caltagirone,et al,Visualization and modeling of acoustic cavitation fields PVP(Am.Soc.Mech.Eng.),1998,377(Computational Technologies for Fluid/Thermal/Structural/Chemical Systems with Industrial Applications,Vol.2),227-234.
    [73]森崎繁.日化.1980:119.
    [74]高木均.水处理技术.1979,20:53.
    [75]Sadana.A.etal.J.Cata.1974,35:140.
    [76]Sadana.A.etal.Ind.Eng.Chem.Fundam.1974,13:127.
    [77]R.T.柯乃普,J.W.戴利,F.G 哈密脱,北京,水利水电科学研究院译,空化与空蚀.[M],水利出版社,1981年9月.
    [78]Kermeen,R.w,McGraw J.T &Parian B.R,Mechanism of caviation inception and the Related Scale-effects problem[J],Tran.ASEM,77,1955,pp;533-541.
    [79]B.E.Nolthingk and E.A.Neppiras,Proc,Soc.B.(London)63 B,(1967)674;64B(1951)1032.
    [80]H.G.Flynn,Physical Acoustics,Vol 1B,ed.W.P.Madon,Academic Press,New York,1964,57-171.
    [81]M.E.Fitzgrald,V.Griffing and J.Sallivan,J,Chem.Phys.25(1956);926.
    [82]黄继汤.空花与空蚀的原理及应用[M].北京:清华大学出版社,1991.
    [83]冯若,黄金兰.超声清洗及其物理机制.应用声学.1994,13(1):42-47.
    [84]丁东.超声清洗声学技术.1983,2(1):60-63.
    [85]钱祖文.《非线性声学》.科学出版社,1992年7月.
    [86]钱盛友,王鸿樟,孙福成.声流现象的研究及其应用,应用声学.1996,16(6):38-42.
    [87]何柞镛等.声学理论基础.北京:国防工业出版社.1981,112.
    [88]王俊.用高能超声法制备的MMCp及其细观力学行为.南京:东南大学,1997.
    [89]Eskin G I,and G S Makarov,Effect of cavitation melt treatment on the structure refinement and property improvement in cast and deformed hypereutectic Al-Si alloys,Materials Science Forum.1997,242:65-70.
    [90]方启平,颜忠余,黄金兰,等用染色法记录液体中大功率超声场的分布,声学技术.1996,15(4),177-179.
    [91]赵茜,高大维.在食品结晶成核中应用超声探讨.食品工业科技.1997,(5):71-72.
    [92]郭志超,李鸿,王静康等.超声波对结晶过程的作用及机理.天津化工.2003,17(3):1-4.
    [93]胡爱军,丘泰球,门杰等,超声场强化溶液结晶研究进展.应用声学,2002,21(4):44-48.
    [94]闫永生,华勤.热分析在铸造检测与控制技术上的应用[J],热加工工艺.2000(1):41-43.
    [95]Jackson K A,Hunt J D,etc.On the origin of the equiaxed zone in castings.TMS-AIME.1966m 236(2):149-158.
    [96]Yue T.M,Ha H.U,Musson N.J.Grain Size effects on the mechanical properties of some squeeze cast light alloys[J].Journal of Materials Science,1995,30:2277-2283.
    [97]范金辉,翟启杰.物理场对金属凝固组织的影响[J].中国有色金属学报.2002,(12):11-15.
    [98]B.S.Murty,S.A.Kori,and M.Chakraborty.Grain refinement of aluminium and its alloys by heterogeneous nucleation and alloying.International Materials Reviews,2002,47(1):3-29.
    [99]S.Y.Sokolov:Zn.Tekh.Fiz.,1936,3(3):176-180.
    [100]Crossley F A,Fisher R D,Metcalfe A G.Viscous shear as an agent for grain refinement in cast metal[J].Trans.Metall.Soc.,AIME,1961,(221):419-420.
    [101]崔衡,苍大强.液态下施加直流电对工业纯铝凝固组织的影响.铸造技术,2006,27(7):729-731.
    [102]訾炳涛,崔建忠等.高密度脉冲电流作用下LY12铝合金的凝固组织[J].特种铸造及有色合金,2000,(4):4-6.
    [103]Nakada M,Shiohara Y,Flemmings M.C.Modification of solidification structure by pulse electric discharge[J].ISIJ Int.,1990,(30):27-33.
    [104]Asai S.Birth and recent activities of electromagnetic processing of materials[J].ISIJ International,1989,29(12):981-992.
    [105]赵学端.粘性流体力学[M].北京:机械工业出版社,1983:13-47.
    [106]李军文,桃野正,付莹.超声波功率对铸锭内的气孔及组织细化的影响[J].铸造技术.2007,(2):152-154.

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