Laser-Welded Steel Foils with Sapphire Substrates

doi:10.1007/s40195-016-0426-x

Abstract

Abstract:

A nanosecond pulsed laser was used to weld stainless steel foils of 10 µm thickness to the sapphire substrates. The microstructure of the bonded interface was studied. Both materials were partially ablated under the influence of the laser beam. An inhomogeneous distribution of the steel and sapphire along the bonded interface is observed. The electrical resistance of the steel foil was measured before and after laser welding, showing that the weld slightly increases the electrical resistance but still keeps the values acceptable for electrical contacts.

Key words: Laser, weldingStainless, steelSapphireElectrical, resistance

Araceli de Pablos-Martín, Christian Grosse, Andreas Cismak, Thomas Höche. Laser-Welded Steel Foils with Sapphire Substrates[J]. Acta Metallurgica Sinica (English Letters), 2016, 29(7): 683-688.

Figures/Tables 10

Fig. 1 Schematic of setup. a Sample consisting in two sapphire substrates (light gray) and the stainless steel foil (dark gray). b The laser beam is focused at the upper sapphire/stainless steel interface. c At the end of the laser process, the bottom sapphire is easily removed and only the upper sapphire remains bonded with the steel foil (for clarity, the sample holder is not shown)

Fig. 2 Top-view optical micrographs of the sapphire/steel interface in the middle of the irradiated line a and showing one of the extremes of the line b. Sapphire substrate is upward

Fig. 3 Top-view optical micrograph of the irradiated line with the stainless steel foil upward

Fig. 4 Optical micrograph of the cross section of the stainless steel/sapphire interface

Fig. 5 SEM micrograph employing a secondary electron detector of the cross section of the stainless steel/sapphire interface a and detailed view of the craters b

Fig. 6 SEM micrograph employing an angle-selective backscattered electron detector (AsB) of the cross section of the stainless steel/sapphire interface. White boxes indicate the areas for the EDXS analysis

Table 1 Element concentration (at.%) from the EDXS analysis at different areas of the interface in Fig. 6 and that of pure stainless steel

Area	Al-K	Cr-K	Fe-K	Fe/Al ratio
1	16.69	16.46	66.85	4:1
2	58.79	10.06	31.15	1:2
3	55.06	9.69	35.25	1:1.5
4	40.76	14.35	44.89	1:1
5	26.33	15.01	58.66	2:1
6	25.30	15.72	58.98	2:1
Stainless steel		18.13	66.55

Fig. 7 Micrograph of the 4-needle setup in one reference stainless steel stripe. The width of the stripes is 800 µm

Fig. 8 Micrograph of the 4-needle setup in one of the laser-welded stainless steel stripes with sapphire. The width of the stripes is 800 µm

Table 2 Resistance values of the reference stripes and those welded with sapphire

Sample	Resistance (m Ω)	Specific resistance (10^-7 Ω m)
Reference	291.17	7.28
Welded foil 1	318.94	7.97
Welded foil 2	297.29	7.43
Welded foil 3	299.91	7.50
Welded foil 4	298.98	7.47
Average value	303.78	7.59

References 27

[1]	J. Ma, Displays 37, 2 (2015)
[2]	N. Marsi, B.Y. Majlis, A.A. Hamzah, F. Mohd-Yasin, Microsyst. Technol. 21, 319(2014)
[3]	X. Chen, D. Brox, B. Assadsangabi, M.S. Mohamed Ali, K. Takahata, in Abstracts of Transducers2015-18th International Conference on Solid-State Sensors, Actuators and Microsystems Alaska,USA
[4]	C.H. Cheng, A.S. Yang, C.J. Lin, W.J. Huang, Microsyst. Technol. (2015). doi:10.1007/s00542-015-2769-z)
[5]	T. Suzuki, I. Kanno, J.J. Loverich, H. Kotera, K. Wasa, Sens. Actuators A 125, 382 (2006)
[6]	Z. Xie, Chem. Phys. Lett. 381, 691(2003)
[7]	X.M. Yu, J.X. Sun, X.L. Zhu, M. Wong, H.S. Kwo, SID Symp. Digest Tech. Pap. 39, 2064 (2008)
[8]	W.-J. Lee, D.-H. Cho, J.-H. Wi, W.S. Han, J. Kim, Y.-D. Chung, Mater. Chem. Phys. 147, 783(2014)
[9]	E.R. Dobrovinskaya, L.A. Litvinov, V.V. Pishchik, USA, 2009)
[10]	L. Qi, K. Nishii, M. Yasui, H. Aoki, Y. Namba, Opt. Laser. Eng. 48, 1000(2010)
[11]	M. Pollnau, in Abstracts of IEEE LEOS Annual Meeting2008 California,USA, pp. 455
[12]	T. Zaharinie, R. Moshwan, F. Yusof, M. Hamdi, T. Ariga, Mater. Design 54, 375 (2014)
[13]	H. Ning, F. Huang, J. Ma, Z. Geng, Z. Han, Rare Metal Mater. Eng. 32, 236(2003)
[14]	C. Varmazis, R. Viswanathan, R. Caton, Rev. Sci. Instrum. 49, 549(1978)
[15]	A. de Pablos-Martín, S. Tismer, T. Höche, J. Mater. Sci.Technol. 31, 484(2015)
[16]	A. de Pablos-Martín, M. Ebert, C. Patzig, M. Krause, M. Dyrba, P. Miclea, M. Lorenz, M. Grundmann, T. Höche, Microsyst.Technol. 21, 1035(2014)
[17]	A. de Pablos-Martin, S. Tismer, G. Benndorf, M. Mittag, M. Lorenz, M. Grundmann, T. Höche, Opt. Laser Technol. 81, 153(2016)
[18]	A. de Pablos-Martín, S. Tismer, F. Naumann, M. Krause, M. Lorenz, M. Grundmann, T. Höche, Microsyst. Technol. 22, 207(2016)
[19]	F.I. Hussein, E. Akman, B. Genc Oztoprak, M. Gunes, O. Gundogdu, E. Kacar, K.I. Hajim, A. Demir, Opt. Laser Technol. 49, 143(2013)
[20]	R.M. Carter, J. Chen, J.D. Shephard, R.R. Thomson, D.P. Hand, Appl. Opt. 53, 4233(2014)
[21]	T. Scholz, K. Dickmann, A. Ostendorf, H. Uphoff, M. Michalewicz, J. Laser Appl. 27, 032001(2015)
[22]	D. Bergström, J. Powell, A.F.H. Appl. Surf. Sci. 253, 5017(2007)
[23]	K. Nagayama, Y. Utsunomiya, T. Kajiwara, T. Nishiyama, in Pulse Laser Ablation by Reflection of Laser Pulse at Interface of Transparent Materials, in Lasers—Applications in Science and Industry, ed. by Krzyszt of Jakubczak (2011)
[24]	M.W. Greenaway, W.G. Proud, J.E. Field, S.G. Goveas, Rev. Sci. Instrum. 73, 2185 (2002)
[25]	S. Chen, J. Huang, J. Xia, H. Zhang, X. Zhao, Metall. Mater. Trans. A 44, 3690 (2013)
[26]	M. Yoshitake, M. Tosa, K. Yoshihara, Thin Solid Films 172, 35 (1989)
[27]	J. Mangas-Murillo, E.M. J. Alloys Compd. 577, 360(2013)