257 Tab.1 The basic compositions of Lead-rich sealing glass ceramics No. ZrSiO 4 Al 2 O 3 ZnO PbO Pb 3 O 4 B 2 O 3 H 3 BO 3 SiO 2 1 [22]

32 2 2011 6 JOURNAL OF CERAMICS Vol. 32, No. 2 Jun. 2011 1000-22782011 02-0256- 13 (α) T f (ρ) Pb PbO Bi 2 O 3 PbO α T f ρ SiO 2 P 2 O 5 B 2 O 3 As 2 O 3 GeO 2 Sb 2 O 3 α T f ρ SiO 2 P 2 O 5 B 2 O 3 As 2 O 3 GeO 2 Sb 2 O 3 Al V Te Mo Se Ti Al 2 O 3 α Tf V 2 O 5 Te Mo Se - TiO 2 α Pb Sn In Tl Bi SnO Tl 2 O 3 In 2 O 3 Bi 2 O 3 α T f ρ - ρ - log (ρ) 150 >10 log(ρ) 20 >15 [5] - - 1 α / α α [1,2] - α T α> 0.5 10-6 / [3] f ρ PbO [6] [3] T g ρ T f [3] 2 R 2 O RO ρ [3] [4] T f glass ceramics 3 ρ - 2011-02- 23 E- mail: rjzeng@xmu.edu.cn

257 Tab.1 The basic compositions of Lead-rich sealing glass ceramics No. ZrSiO 4 Al 2 O 3 ZnO PbO Pb 3 O 4 B 2 O 3 H 3 BO 3 SiO 2 1 [22] - 2.0 10.0 75.0-10.0-3.0 2 [22] 4.8 1.4 11.4 71.3-8.4-2.6 3 [13] - 3.85~8.93 - - 56.52~76.92-15.38~26.79 3.85~4.76 8 1000 ppm [24] 0.1 wt.% 1.3.1 [25] α T f ρ 2007 3 [7] PbO PbO [26] 60~80 wt.% PbO 2010 [8,9] α [10,11] 1 1 PbO Tf [12] α T f ρ [13] Pb 3 O 4 Pb 3 O 4 Pb 4+ [27] [PbO 6 ] Pb 2+ [14] [PbO 3 ] Pb 4+ Pb 2+ Pb 4+ [O] Pb 2+ α T f ρ [7] Pb 4+ [PbO 4 ] [7] Pb 3 O 4 [PbO 4 ] [SiO 4 ] Pb 2+ [7] α ρ R 2 O RO [ 3] [15-17] PbO [5,10,12, 28-36] PbO-B 2 O 3 [5,32-34] V R 2 O-PbO-B 2 O 3 -SiO 2 (R=Li,Na,K),F-Al 2 O 3-2 O 5 V 2 O 5 - P 2 O 5 [31,37,38] ZnO- SnO PbO-B 2 O 3 -SiO 2,ZnO-PbO-B 2 O 3 -SiO 2, RO-PbO- AB1953 [2, 3, 18-21] B 2 O 3 -SiO 2 (R = Ca, Ba, Sr) ZnO- - P 2 O 5 [39-41] [ 22, 23] PbO- B 2 O 3 α 5.5 10-6 ~9.0 10-6 / SiO 2 500~650 PbO 1 α T f ρ - 1.3.2 Bi 2 O 3 2006 7 1 RoHS Bi 2 O 3

258 SiO 2 SiO 2 [6] [42] - Philips SiO 2 2 SiO 2 [SiO 4 ] [6] α T f R 2 O RO T f α R 2 O RO R 1+ R 2+ ρ [3,6] [42] - Philips α 9.3 10-6 / - α 11 10-6 / T f 650 T f ρ log(ρ) 250 = 8.85 log(ρ) 350 = 7.00 R 2 O RO ρ [5,32] [42] - Philips Bi 2 O 3 Bi 2 O 3 - - α 2 SiO 2 α Ghosh [43] α SiO 2 α 3 650~700 [43] 3 BaO- CaO- Al 2 O 3 - SiO 2 α T f ρ BCAS BCAS2~BCAS5 SiO 2 28.2 wt.% Ghosh Pb Sn In Tl Bi 5.72 10 3 Kg/m 3 SiO 2 1 SiO 2 [43] BaO B 2 O 3 P 2 O 5 [44] V 2 O 5 Al 2 O 3 [6] α Ghosh Ghosh SiO 2 BCAS 3.90 10 3 Kg/m 3 SiO 2 BCAS 2.3.1 SiO 2 3.3 10 3 Kg/m 3 SiO 2 BCAS 1 SiO 2 Al 2 O 3 BaO CaO Tab.2 The basic composition of SiO 2 -rich sealing glass ceramics (wt.%) Li 2 O Na 2 O K 2 O CaO SrO BaO MgO Al 2 O 3 SiO 2 SO 3 α( 10-6 /, 25~300 ) T f ( ) 1.2 7.4 5.0 1.9 2.9 8.7 1.3 3.4 68 0.1 9.25 675

259 α Tab.3 The basic composition and α of SiO 2 -rich sealing glass ceramics in the BaO-CaO-Al 2 O 3 -SiO 2 system (wt.%) Other No. BaO CaO Al 2 O 3 SiO 2 ingredients α 10-6 / RT*~T g log(ρ) 750 T g ( ) Density (g/cm 3 ) BCAS1 35.0 15.0 0 44.0 6.0 9.2 6.87 665 3.33 BCAS2 50.0 7.8 4.8 28.1 9.3 11.2 6.75 623 3.82 BCAS3 52.9 8.8 5.1 25.3 7.9 11.6 6.45 611 3.86 BCAS4 55.6 9.2 5.5 25.3 4.4 11.9 6.38 609 3.89 BCAS5 57.4 8.8 5.4 22.1 6.3 12.4 5.25 608 3.93 Tab.4 The basic composition of SiO 2 -rich sealing glass ceramics in the Li 2 O-ZnO-SiO 2 system(wt.%) No. Li 2 O Na 2 O MgO Sb 2 O 3 ZnO SiO 2 B 2 O 3 P 2 O 5 1 [40] 9 5 3 0.3 24.1 54.2 5 2.4 2 [41] 9 5 3 0.4 21 58.2 1 2.4 [O] Al 2 O 3 [AlO 4 ] [PO 4 ]4 1 [44,45] RO P=O R 2 O ρ [6,46] BaO CaO P 2 O 5 P=O R 2 O ρ [PO 4 ] 3 [PO 4 ] 4 [46] Ghosh log(ρ) 750 BaO BaO [35] T g 3 T f P 2 O 5 α T f T g [47] α 12.4 10-6 [12,31] / ρ α α T f ρ [36] [39-41] [31,36] SiO 2 SnO T f [5,36] MgO- Al 2 O 3 - SiO 2 α 1.8 Sn 2+ 10-6 ~3.9 10-6 / [39] P 2 O 5 Li 2 O- ZnO- SiO 2 α 11.8 10-6 ~16.1 10-6 / SiO 2 B 2 O 3 Al 2 O 3 [40, 41] 1010 α α T f [31] P 2 O 5 4 ρ 4 ZnO- SnO- P 2 O 5 [3] R 2 O RO ρ - 2.3.3 B 2 O 3 2.3.2 P 2 O 5 B 2 O 3 [35] P 2 O 5 B 2 O 3 [PO 4 ] SiO 2 V 2 O 5

260 Bi 2 O 3 SnO 4 ~ 6 B 2 O 3 TiO 2 α [42] B 2 O 3 - SiO 2 α TiO 2 T f [35,36] α T f ρ RO R 2 O α Te T f ρ [3] [33] α R 2 O- Tl 2 O 3 - TeO 2 - V 2 O 5 - P 2 O 5 [ 5] T f ρ - TeO 2 Tl 2 O 3 [5,34,53] 2.3.4 V 2 O 5 [33] [VO 6 ] [44,48] [54] GeO 2 As 2 O 3 Sb 2 O 3 V 2 O 5 [33,34] GeO 2 [49] GeO 2 V 2 O 5 Tl Te [33,34] As 2 O 3 Sb 2 O 3 R 2 O- Tl 2 O 3 - TeO 2 - V 2 O 5 - P 2 O 5 [44] [50] As 2 O 3 Tl 2 O 3 TeO 2 Tl 2 O 3 TeO 2 ZnO- V 2 O 5 - B 2 O 3 [33,34] 2.3.5 T f [55] Al V Bi Te Mo Se Ti - [44] Mo [51] Se [52] [55] 362~370 β- β- eucryptite α α 7.5 10-6 / [33] [56] Al 2 O 3 Al- O Al 2 O 3 V 2 O 5 α [46] V 2 O 5 [56] [33] α T f ρ SiO 2 V 2 O 5 - V 2 O 5 [46] Al 2 O 3 - α - - PDP VFD Al 2 O 3 Sb 2 O 3 - V 2 O 5 - P 2 O 5 T f [33] V 2 O 5 5 [7, 46] TiO 2 2.3.6 SnO [45] TiO 2 [45,46] [O] Ti α Sn Pb [46] Sn 2+ TiO 2 α - Pb 2+ SnO Tab.5 The basic composition of V 2 O 5 -rich sealing glass ceramics (wt.%) No. Sb 2 O 3 Al 2 O 3 ZnO V 2 O 5 B 2 O 3 P 2 O 5 β- eucryptite α( 10-6 /, RT~350 Tf ( ) 1 10.0 - - 58.0 0.5 31.5 20.0 7.0 362 2 6.0 2.0 1.0 60 1.0 30 28.0 7.2 365

261 Tab.6 The basic composition of SnO-rich sealing glass ceramics in the SnO-ZnO-P 2 O 5 system (wt.%) No. SnO Al 2 O 3 ZnO P 2 O 5 SiO 2 α ( 10-6 / RT~250 ) T f T g 1 [37] 53-5 35 7 12.1-287.3 2 [60] 48.7 1 18.3 32-10.1 339.5 319.0 - - - - - B 2 O 3 - - - 3 [60] 48.7 1 18.3 29 3 9.54 354.7 329.8 - SnO 2 - - - - - - * 4 [59] 50.9-13.7 35.4-10.4-278 Sn 2+ Sn 2+ Pb 4 In 0.1 mg/m 3 [61] In 2 O 3 [62] SnO In SnO In 2 O 3 [10] SnO T f In 2 O 3 α [6] SnO Sn 4+ 2.3.8 Tl 2 O 3 Sn 2+ Sn 4+ Tl Pb Pb [61] SnO 2 Tl 2 O 3 Tl 2 O 3 [57] SnO 2 R 2 O- TeO 2 - Tl 2 O 3 - V 2 O 5 - P 2 O 5 [34] Sn 4+ [5,34,53] Tl 2 O 3 TeO 2 [37] - [33] 90 SnO- ZnO- P 2 O 5 SZP [58,59] - [58,59] [59] - 2.4.1 SnO 2 SnO 2 Bi Pb SZP Bi 3+ Pb 2+ [12] [31] [37,,38,57,60] [37] [60] SiO 2 Al 2 O 3 B 2 O 3 Bi Pb 6 Bi 3+ As 2+ Sb 2+ 6 T f α Sn 2+ Bi 3+ [12] SnO 50wt.% Bi 2 O 3 [5,31] ρ [44] Bi- O - SnO Bi 3+ [AsO 3 ][SbO 3 ] [58,59] [12] - - [BiO 3 ] [63] 2.3.7 In 2 O 3 Bi 2 O 3 α T f ρ In Pb Bi 2 O 3 [8

262 Tab.7 The basic composition of leadless Bi 2 O 3 -rich sealing glass ceramics (wt.%) No. Na 2 O CeO 2 Al 2 O 3 ZnO Bi 2 O 3 B 2 O 3 SiO 2 α ( 10-6 / RT~250 ) T f ( ) T g ( ) 1 [65] - 0.4-13.9 79.8 5.9-7.0-350 2 [70] 5 4.61 0.4 5.8 83 10.4 8 9.8 400 335 - CaO - - - - - - - - - 3 [69] 3.5-4.0 5.4 73.0 9.5 4.6 9.0 473 432 - - MgO - - - H 2 BO 3 - - - - 4 [68] 2 1.5-2.5 73 15 7 8.8 485 450 [9] Bi 2 O 3 [71] Bi 2 O 3 BaSO 4 X Bi 2 O 3 BaO Ba 2+ BaO Ba 2+ Bi 2 O 3 Bi 3+ Bi 2 O 3 [38] BaO Ba 2+ [65,66] Bi 2 O 3 [22,38] Bi 2 O 3 Bi 3+ BaO Ba 2+ RoHS Bi 2 O 3 Pb [24-26] Bi 2 O 3 Bi 3+ [44] Bi 2 O 3 Bi 2 O 3 [64] BaO / AGC Asahi Glass Co., Ltd. Bi 2 O 3 - - K301~304 K807~834 BaO www.agc.com Bi 2 O 3 α T f ρ Bi 2 O 3 Bi 2 O 3 3 CuO ZnO- Bi 2 O 3 - B 2 O 3 2.4.2 Bi 2 O 3 [7] Bi 2 O 3 Bi 2 O 3 α T f [72] [65,66] [11,67] 2.4.3 Bi 2 O 3 [68,69] 7 Bi 2 O 3 Schott AG - RO R 2 O ρ [67] - 8350 α SiC 7.2 10-6 / ~300 T f 715 log(ρ) 350 = 5.7 Bi 2 O 3 [68,69] http://www.schott.com ρ

263 ρ - 3.1.2 ρ [11,67] 2 h DM- 305 - α 5 10-6 / 20~300 T f 993 http://baebj. com α T f α 3.1.3 Bi 2 O 3 AGC Bi 2 O 3 [69] http://www.agc.com 3.2 3.1.4 Parkathings Amorphous Material Technology Co., Ltd, Xiamen, PAM 2.4.4 Bi 2 O 3 3. 1.5 Bi 2 O 3 α T f ρ - [73,74] ZnO [76] 7 Bi 2 O 3 PbO 380 Bi 2 O 3 81.2~90.5 wt.% / 2h [11] Bi 2 O 3 465 2h [67] [11,69] Bi 2 O 3 Bi 2 O 3 1 T f T f Bi 2 O 3 [75] 2 2 PbO Bi 2 O 3 polyvinylalcohol PVA polyvinyl b utyral [69] PVB α T f ZnO B ρ PbO Bi 2 O 3 2 O 3 PVA [31] PVA PVB [69] TG 3.1.1 PbO Bi 2 O 3 2h [67,69] charred

264 α ρ Fig.2 Lead-free sealing glass ceramic samples with high α, low T f and high ρ, prepared by the author's research group θ Fig.3 XRD patterns of Bi 2 O 3 -rich glass and glass ceramics prepared by the author's research group [77] [69,77] 1.1 α [2,3,20] 1000 2h [11,67] B 2 O 3 450 [46, 61] MgO [46,78] B 2 O 3 AGC AGC B 2 O 3 B 2 O 3 LX430LX Incolloy800 α 10.7 K 2 O PbO B 2 O 3 10-6 ~12.1 10-6 / 16.2 10-6 ~18.0 10-6 / [46] [46,79] [80] α 10.7 10-6 ~18.0 10-6 / [46,79] [46] T f ρ B 2 O 3 11wt.%B 2 O 3 7 α SZP [81] [30] wt.% ~15wt.%B 2 O 3 Bi 2 O 3 α RO R 2 O B 2 O 3 7 10-6 ~8 10-6 / Bi 2 O 3 α 8.0 10-6 ~12.0 10-6 / [67 69] Bi 2 O 3 α 12.0 10-6 / [11] - XRD 3 XRD a ρ 2θ=27 o Bi 2 O 3 R 2 O RO [67,69] Bi 2 O 3 b ρ α T f [67,69] Bi 2 O 3 [71] 4 Bi 2 O 3 [69] T f 482 ρ Bi 2 O 3

265 ρ Ω α Fig.5. Variation of α with temperature for a sample prepared by the author's research group ρ Fig.7 Variation of ρ with temperature for samples prepared by the author's research group R 2+ R 1+ 5 B 2 O 3 ρ α SiO 2 α T f ρ T f 5 α T f ρ Bi 2 O 3 ρ log(ρ) 250 B 2 O 3 SiO 2 SnO V 2 O 5 log(ρ) 350 10 Bi 2 O 3 Bi 2 O 3 ρ GeO 2 As 2 O 3 [69] Bi 2 O 3 Sb 2 O 3 [69] 6 V 2 O 5 V 2 O 5 Al 2 O 3 α α T f ρ TiO 2 1 PbO α T f α α T f ρ ρ Te Mo 2 SiO 2 Se - SiO 2 60~72 wt.%philips R 2 O RO α ρ T f 7 SnO SnO 3 SiO 2 3~4 SnO 2 SiO 2 22~58 wt.% BaO CaO - BCAS ρ 8 In 2 O 3 Tl 2 O 3 - Tl 2 O 3 In 2 O 3 4 P 2 O 5 α T f 9 Bi 2 O 3 V 2 O 5 Tl 2 O 3 α T f ρ Bi 2 O 3

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268.,1998,1(2):197~200 80 SNYDER M J, MESKO M G, SHELBY J E. Volatilization of boron from E- glass melts. Journal of Non- Crystalline Solids, 2006, 352: 669~673 81 МАТВЕЕВ М A,МАТВЕЕВ Г М,ФРЕНКЕДЪ В Н.Расчеты по Химии и Технологии Стекла.Москва:Издательство литературы по строительству,1965,.. :,1978 Lead-Free Sealing Glass Ceramics with High Thermal Expansion Coefficient, Low Softening Temperature and High Electrical Resistivity: An Overview DU Zhenbo GAO Shengxia ZENG Renjie (College of Materials, Xiamen University, Xiamen Fujian 361005, China) Abstract The research and development profiles and prospects of lead -free sealing glass ceramics with a high thermal expansion coefficient (α), low softening temperature (T f ) and high electrical resistivity (ρ) have been reviewed. The possibility of replacing PbO with some oxides (In 2 O 3, SnO, Tl 2 O 3 or Bi 2 O 3 ), the metal elements of which are near Pb or in its diagonal positions in the periodic table, or of replacing lead-rich system by either common glass forming oxides (e.g. SiO 2, B 2 O 3 or P 2 O 5 ) or conditional glass forming oxides (e.g. V 2 O 5 or TeO 2 ), has been intensively discussed, respectively. The ingredients, preparation techniques and properties of the Bi 2 O 3 -rich system have been fully discussed. It has been concluded that a high α, low T f, and high ρ could be obtained in a lead-rich system which had been, already, forbidden to be used in domestic appliance by law for its harm to the environment. The lead-free system rich in SiO 2, P 2 O 5 or B 2 O 3 could not, unfortunately, obtain the required properties at the same time; rich in other common glass forming oxides may be unsuitable for domestic appliance application due to its high cost (e.g. GeO 2 ), toxicity (e.g. As 2 O 3 ), or being difficult for preparation (Sb 2 O 3 ). The leadfree system rich in conditional glass forming oxides may be not suitable for domestic appliance application due to its toxicity (e.g. V 2 O 5 ), or high cost (the oxides of Te, Mo or Se); the glass containing Al 2 O 3 may be unsuitable for preparing a sealing glass ceramic due to its low α and high T f ; and the glass containing TiO 2 may be unsuitable for preparing a sealing glass ceramic due to its low α and easy crystallization. The lead-free system rich in In 2 O 3, SnO or Tl 2 O 3 may be restricted either due to their toxicity (e.g. Tl 2 O 3 ), high cost (e.g. In 2 O 3 ) or the difficulty in preparation (SnO); whereas Bi 2 O 3 -rich system could meet all the requirements as mentioned above, and, therefore, have a bright prospect to be used in for domestic appliance. Key words melting point; bismuth trioxide; solder; metal; heater Received on Feb. 23,2011 ZENG Renjie,E-mail: rjzeng@xmu.edu.cn