[雙語翻譯]--外文翻譯--鋁銅復(fù)合板中斷裂機(jī)制、冷軋結(jié)合后結(jié)合鍵強(qiáng)度對于復(fù)合板界面的影響（英文）

1、Influence of Interfacial Structure Development on the Fracture Mechanism and Bond Strength of Aluminum/Copper Bimetal PlateChih-Yuan Chen1;*, Hao-Long Chen2 and Weng-Sing Hwang11Department of Materials Science and Engine

2、ering, National Cheng Kung University, Tainan 701, Taiwan, R. O. China 2Department of Electronic Engineering, Kao Yuan University, Kaohsiung County 821, Taiwan, R. O. ChinaThe aim of this article is to study the influenc

3、e of interfacial structure development at interface on the fracture mechanism and the bond strength of cold roll bonded Al/Cu bimetal plate. The Al/Cu bimetal plates are produced by cold roll bonding and then sintered at

4、 different conditions. The bond strength of the Al/Cu bimetal plate increases generally to maximum values and then decreases to low values with increasing sintering temperature and time. Interfacial structures develop wi

5、th increasing sintering temperature and time. The main interfacial layers are Al2Cu, AlCu, Al3Cu4 and Al4Cu9. The formation and thickening of those intermetallic compounds promotes cracks propagation and weakens the bond

6、 strength of the bimetal plates. The fracture mechanism transforms from ductile to brittle cleavage with the development of interfacial structures. While the bond strength of the material starts to decrease, no obvious K

7、irkendall effect of void formation is observed in the present study.(Received January 17, 2006; Accepted February 20, 2006; Published April 15, 2006)Keywords: bimetal, cold roll bonding, intermetallic compound, bond stre

8、ngth, fracture mechanism1. IntroductionClad metal materials have become increasingly popular for industrial applications in recent years, such as Al/Cu, Cu/ SUS, Cu/Ag, Al/Ni, Steel/Ti, etc.1–4) They sometimes possess en

9、hanced mechanical properties and corrosion resistance. Metallurgical bonding Al to Cu is widely used as a transition piece in high direct-current bus systems to transmit electricity.5) Thus the bonding properties of the

10、material have a great influence on its electrical properties. From the viewpoint of the metallurgy in the bonding process, Al and Cu are incompatible metals because of high diffusion affinity to each other at temperature

11、s above 120?C that results in the formation of intermetallic compounds that are brittle, and with high electric resistance on their interfaces.6,7)Therefore, fusion-welding processes are not applicable for bonding of Al

12、to Cu. The clad metal can be produced by some solid-state welding such as explosion welding, friction stir welding, diffusion bonding, or co-axial extrusion. However, the most economic and productive manufacturing proces

13、s for large size flat clad metal sheets and foils is roll bonding. Roll bonding is a well-established and widely used solid state welding process to join dissimilar metals. Compared with hot roll bonding, cold roll bondi

14、ng has several advantages, including more uniform individual layer thickness ratio, good surface quality and lower oxidation during bond process, which makes it suitable to be applied on some ductile metals like Al and C

15、u.8,9) After the roll bonding process, a sintering treatment is usually applied to enhance the bonding strength of the materials. The post sintering treatment generally governs both the bond strength and mechanical prope

16、r- ties.10,11) Some previous investigations have revealed that the process parameters have a crucial influence on the final properties of the Al/Cu bimetal plate. Those process parameters including surface preparation, r

17、olling reduction, rolling temperature, sintering temperature and time, signifi-cantly affect the bond strength. According to some previous studies on the mechanism producing metallic bonding in the roll bonding process,

18、surface scratch-brushing is a partic- ularly effective form of surface preparation for cold rolling because of its higher surface decontaminating effect and the production of suitable surface roughness. Higher cold reduc

19、tion provides plastic deformation energy to create more effective bonding areas in cold roll bonding,12,13) and the bond strength could be enhanced at suitable roll bonding temperature.14) Some studies on the roll bondin

20、g of Al/Cu bimetal laminates show that the interfacial reactions that occur in the sintering process, named interfacial phase transformations and Kirkendall void formation, dominate the variation of bond strength. As the

21、 sintering time and/or temperature increase, the Kirkendall effect becomes more significant with the agglomeration of voids, which leads to the formation of weak layers in the interface region.15–17)In this study, Al/Cu

22、bimetal plates are made using cold roll bonding. The development of interfacial structure is per- formed and identified at different sintering conditions. The objectives of the present study are to investigate the influe

23、nce of the development of the intermetallic compound on mechanical properties during sintering treatment under various temperatures and times. The relation between the interfacial development and fracture mechanism provi

24、des valuable information in controlling process parameters.2. Experimental Procedure2.1 Fabrication of Al/Cu bimetal plates The metal sheets used in this study were pure copper (C11000) with the primary dimensions of 300

25、 ? 65 ? 0:8 mm, and aluminum (AA1050) 300 ? 650 ? 2 mm, which were shown in Table 1. Cold roll bonding process was carried out using a laboratory rolling mill with a roll road capacity of 200 tons. The roll diameter was

26、400 mm and the roll speed was about 10 m min?1. The Aluminum and Copper sheets were polished both mechanically and chemically in the *Graduate Student, National Cheng Kung UniversityMaterials Transactions, Vol. 47, No. 4

27、 (2006) pp. 1232 to 1239 #2006 The Japan Institute of Metals EXPRESS REGULAR ARTICLEHigher reductions are found to generate a greater amount of heat and create more cracks at the contact surfaces of both metals being joi

28、ned, which benefit bond strength,9) as shown in Table 2.3.2 Bonding strength evolution of Al/Cu bimetal plate After the initial bonding produced by cold roll bonding, post heat treatments are applied to quicken the devel

29、opment of metallurgical joints and create a common lattice structure. Peel test is carried out to investigate how the bond strength varied with different sintering conditions. The peel strength (N cm?1) at different sint

30、ering conditions was determined. Figure 6(a) shows the typical peel strength vs. crosshead displacement curves at a cold reduction of 57%. The tendency of all test curves drops with increasing crosshead displacement, whi

31、ch is attributed to the fact that the bond strength of the Al/Cu bimetal plate is smaller than the stiffness of the Al and Cu plate. While cracks propagate, the crack tip deviates away from peel axial and forms a lever t

32、o peel the bimetal plate, as shown in Fig. 6(b). Figure 7 shows the variation of break-off peel strength with respect to sintering time at the sintering temperatures of 250 to 500?C. It is apparent that the samples sinte

33、red at 250?C generally have higher break-off peel strength than those sintered at 300, 400, and 500?C. As the sintering time increases, break-off peel strength of the Al/Cu bimetal plate increases to amaximum values and

34、then decreases. With increasing sintering temperature, the maximum value decreases and sintering period decreases. This may be attributed to the higher relaxation of the mechanical locking for materials sintered at highe

35、r temperature.Brittle/hardening layerCu-sideVirgin metal jointed at cracksnon-bonded areaAl-sideFig. 4 Fracture morphology of as-rolled specimen Cu-side and Al-side for a cold reduction of 57%.(a)200 µ m 200 µ

36、m 200 µ m(c) (b)Fig. 5 Available bonding areas (cracks) at different cold reductions (a) 45%, (b) 57%, (c) 66%.Table 2 Relationship between break-off peel strength available bonding areas.Cold reduction (%) 45 57 66

37、Break-off peel strength (N/cm) 32.3 65.9 107Available bonding areas (%) 10.1 18.8 40.5(a)0 10 20 30 40 Crosshead dispalcement, d/mm020406080100Peel strength, σ /N.cm-1250oC-30minBreak-off peel strength300oC-30min450oC-30

38、min500oC-30min500oC-60minas-rolledAlCuPeel forcePeelCrack tipPeelCrosshead displacementCrack tipPeelForm a lever to peel sample AlCu(b)Fig. 6 (a) The typical peel strength vs. crosshead displacement curve, and (b) sche