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Ag–Ti composites fabricated by liquid sintering
Materials Letters 116 (2014) 212–214
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Materials Letters journal homepage: www.elsevier.com/locate/matlet
Effects of Ti addition on thermal properties of diamond/Ag–Ti composites fabricated by liquid sintering Mu-Tse Lee, Chih-Yu Chung, Chun-Ming Lin, Su-Jien Lin n Department of Materials Science and Engineering, National Tsing Hua University, Hsinchu 300, Taiwan
art ic l e i nf o
a b s t r a c t
Article history: Received 13 September 2013 Accepted 1 November 2013 Available online 9 November 2013
Diamond/Ag–Ti composites were fabricated by a low-cost vacuum liquid sintering technique and the effects of Ti addition on the thermal properties of the composites were studied. The results indicate that the optimal quantity of added Ti is 3 at%. Adding less than 3 at% Ti resulted in poor wettability, while adding more than 3 at% Ti resulted in excessive formation of TiC. Both reduced thermal conductivity. A composite comprising 60 vol% diamond/Ag–3at%Ti resulted in a maximum thermal conductivity of 836 W m 1 K 1 with a coefficient of thermal expansion of 5.6 10 6 K 1 . These composites are excellent candidates for the thermal management of integrated electronic devices. & 2013 Published by Elsevier B.V.
Keywords: Microstructure Interfaces Thermal properties Composite materials
1. Introduction Thermal management is an important issue in the development of electronic devices with high power density requirements [1,2]. The efficient removal of heat from high density integrated circuitry depends upon two essential factors: thermal conductivity (TC) and the coefficient of thermal expansion (CTE). The TC of heat spreading/sinking materials must be as high as possible and the CTE must equal that of the materials of which the semiconductors are composed, such as Si, InP, and GaAs (CTE range 4–7 10 6 K 1) [3,4]. Diamond-based metal matrix composites (MMCs), such as diamond/Cu, diamond/Al, and diamond/Ag, have attracted considerable attention as heat-spreading materials [3,5–11] due to their high TC and CTE, which can be tuned to match that of the semiconductors. A challenge associated with diamond-based MMCs is the cost of the equipment required for processes such as metal infiltration [7,9,12], hot pressing [13], hot isotactic pressing [14], and spark plasma sintering (SPS) [4,15,16]. Eliminating the need for expensive equipment is essential for the mass production of high TC diamond-based MMCs. Another challenge is the poor wettability between the metal matrix and diamond. The addition of carbide-forming metal into the matrix, such as Cr, B, Zr, or Ti [5,10,17,18], can improve the wettability [2,6,13]. Ensuring high TC requires that the carbide interlayer be continuous and thin [2,18]. However, few studies have investigated the quantity effect of carbide-forming element. This paper
n
Corresponding author. Tel.: þ 886 3571 5131x342620; fax: þ 886 3572 2366. E-mail address: [email protected] (S.-J. Lin).
0167-577X/$ - see front matter & 2013 Published by Elsevier B.V. http://dx.doi.org/10.1016/j.matlet.2013.11.001
presents a low-cost cold pressing and vacuum liquid sintering process to fabricate the diamond/Ag–Ti composites and the effects of Ti addition on the thermal properties of the composites were studied. 2. Experimental Silver powder (99.99 wt% in purity, Agpro) with an average size of 5 μm and Ti powder (99.9 wt% in purity, Unionward) with an average size of 35 μm and diamond particles (YK-9E with the thermal conductivity of 1800 W m 1 K 1, Fine Abrasives, Taiwan) with an average size of 300 μm were mechanically mixed and cold-pressed at 700 MPa for 20 min. The compacted composite was then sintered in a vacuum (base pressure ¼4.5 10 2 Torr) with 30 sccm H2 at 1278 K for 30 min. The microstructure was observed by a scanning electron microscope (SEM; JEOL-5410, Japan). The crystal structures were identified by an X-ray diffractometer (XRD, Rigaku, Japan) using Cu Kα radiation with the operating voltage and current of 30 kV and 20 mA, respectively. Thermal diffusivity (D) and specific heat (C) were measured using a laser flash analyzer (Netzsch LFA 447, Germany), while thermal conductivity (K) was determined according to the relationship K ¼D ρ C, where ρ is the density of the composite. The theoretical densities of pure silver (10.5 g cm 3), pure titanium (4.5 g cm 3) and diamond (3.52 g cm 3) were used to calculate the relative density of samples. In the experiment, the densities of the composites were measured according to Archimedes’ law and compared with theoretical densities to obtain the relative densities. The coefficients of thermal expansion (CTEs) were measured using a thermal analysis apparatus (TA Instruments, TMA 2940, U.S.A.)
M.-T. Lee et al. / Materials Letters 116 (2014) 212–214
at a heating rate of 10 K min 1 from 298 K to 423 K. Focused ion beam (FIB, FEI-Nova 200) technology was used for the preparation of samples prior to observation under transmission electron microscopy (TEM) was performed using a JEOL JEM-2100 electron microscope operated at 200 kV. 3. Results and discussion Fig. 1 presents surface SEM images of the 60 vol% diamond composites with various proportions of Ti added to the Ag matrix. We have studied 50 vol%, 60 vol% and 70 vol% diamond composites, and we found that 60 vol% exhibit the highest TC. At 1 at% Ti, the composite presented a number of voids, indicating poor wettability due to insufficient Ti content. The composites produced with 3 and 5 at% Ti both presented good wetting behavior to the surface of the diamonds. This wetting behavior of the Ti promoted the wettability of the Ag to the diamond [5,19]. These results are in line with those of previous studies [19]. Fig. 2 presents the X-ray diffraction spectra of composites produced with 60 vol% diamond within an Ag–3 at% Ti matrix. The diffraction peaks in Fig. 2a can be attributed to diamond, Ag, TiAg, and TiC, Ag and TiAg peaks nearly overlap [17], indicating that the lattice constants of Ag and TiAg are similar. XRD analysis confirms the successful fabrication of diamond/Ag–Ti composites without impurities. These results also confirm the formation of TiC during the sintering process following the addition of Ti to the Ag matrix. Fig. 2b presents a backscattered electron image (BEI) of the same sample as well as element mapping by energy dispersive spectroscopy (EDS), showing Ti-rich areas on the diamond sites. These results show that most of the Ti appeared on the surface of the diamond particles, indicating the preference of Ti for diffusion bonding with diamond, rather than with the Ag matrix.
213
Fig. 3 presents the curves representing Ti content within the matrix versus TC and the relative density of the diamond/Ag–Ti composites. The relative densities of the composites increased with an increase in Ti content from 1 at% up to 3 at% Ti, remaining relatively high ( 498.4%) until 5 at%. The presence of pores reduced densification to only 97.4% when the Ti content was 1 at%. This phenomenon can be attributed to the relatively low Ti content, causing inefficient wetting of the diamond interfacial area (see Fig. 1). The reduction in relative density subsequently reduced the TC of the composites [14,20]. The CTE measurements of diamond/Ag–Ti composites were 6.9, 6.4, 5.6, 5.6, and 5.7 10 6 K 1 for 1, 2, 3, 4, and 5 at% Ti additions, respectively. The CTEs of the diamond/Ag–Ti composites decreased with an increase in Ti content and remained at 5.6 10 6 K 1 when the Ti content was 3 at% or higher. These results indicate that 3 at% Ti is sufficient to improve wettability and bonding between the diamond reinforcement and Ag matrix. Fig. 3 presents the TC values of the diamond/Ag–Ti composites (578–836 W m 1 K 1). These considerably high values demonstrate the potential of the proposed vacuum liquid sintering technique for the fabrication of diamond/Ag–Ti composites. Fig. 3 also illustrates an increase in TC for composites with Ti content up to 3 at%, that followed by a decrease for composites with Ti content above 3 at%. These figures illustrate the trade-off between wettability and total TC in the diamond/Ag–Ti system. The wettability of the diamond/Ag interface increased with an increase in Ti content from 1 to 5 at% Ti (Fig. 1). However, the TC of the composite decreased when more than 3 at% Ti was added, due to an increase in TiC with low TC (27 W m 1 K 1) [21]. The TC of the diamond/Ag–3 at% Ti composite was as high as 836 W m 1 K 1, which similar that of diamond/Ag composites fabricated by spark plasma sintering (SPS) [16].
Fig. 1. SEM surface images of the 60 vol% diamond/Ag composite sintered at 1278 K with different Ti composition in the matrix from 1 at%, 3 at% and 5 at%.
Fig. 2. (a) X-ray diffraction pattern, (b) the BEI surface image and its corresponding EDS element mappings of Ag, C and Ti for the 60 vol% diamond/Ag–3 at% Ti composite.
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M.-T. Lee et al. / Materials Letters 116 (2014) 212–214
patterns matched the standards of titanium carbide (TiC), as shown in the insert of Fig. 4a. The formation of TiC on the surface of the diamond particles provides evidence of the enhanced wettability of the diamond/Ag–Ti composites.
4. Summary
Fig. 3. Ti content vs. TC and relative density of 60 vol% diamond/Ag–Ti composite.
Diamond/Ag–Ti composites were fabricated by a low-cost cold pressing followed by vacuum liquid sintering and the effects of Ti addition on the thermal properties of the composites were studied. The addition of Ti to the Ag matrix increased the wettability and adhesion of Ag to the surface of the diamond particles through an interface reaction, resulting in the formation of Ti-rich layer. This improvement in wettability improved the density of the resulting materials and subsequently enhanced the thermal properties of the composite. The optimal quantity of added Ti is 3 at%. Adding less than 3 at% Ti resulted in poor wettability, while adding more than 3 at% Ti resulted in excessive formation of TiC. Both reduced thermal conductivity. A composite comprising 60 vol% diamond/Ag–3 at%Ti resulted in a maximum thermal conductivity of 836 W m 1 K 1 with a coefficient of thermal expansion of 5.6 10 6 K 1. These composites are excellent candidates for the thermal management of integrated electronic devices.
Acknowledgement The authors would like to thank the National Science Council, Taiwan, R.O.C. for the support of this research through the project No: NSC-102–2221-E-007-046-MY3. References
Fig. 4. TEM bright field image (insert is the selected area diffraction pattern of Tirich area) and its corresponding element mappings of C, Ag and Ti of the diamond/ Ag interface cut from the surface of 60 vol% diamond/Ag–5 at% Ti composite.
[1] [2] [3] [4] [5]
According to the above results, we can conclude that the optimal Ti content addition is 3 at% for the 300 μm diamond/ Ag–Ti composites. Adding less than 3 at% Ti resulted in poor wettability, while adding more than 3 at% Ti resulted in excessive formation of TiC. Both reduced thermal conductivity. Improving the wettability resulted in higher relative density ( 498.4%) and lower CTE ( 5.6 10 6 K 1). However, the formation of excessive TiC reduced the TC, due to the low TC of TiC. The interfacial structure and elemental distribution were further characterized by TEM mapping to check the TiC peaks and Ti distribution, as shown in Fig. 4. Three distinct elemental distributions were observed: diamond, a Ti-rich layer, and the Ag– Ti region. The Ti-rich layer was approximately 1000 nm in thickness and contained a layer (approximately 150 nm in thickness) containing both Ag and Ti. This Ti-rich layer was produced by diffusion and its presence is consistent with the observations of previous studies [22,23]. The major constituents of the Ti-rich layer were identified by TEM. Selected area diffraction (SAD)
[6] [7] [8] [9] [10] [11] [12] [13] [14] [15] [16] [17] [18] [19] [20] [21] [22] [23]
Zweben C. J Metal 1998;50:47–51. Zweben C. Adv Mater Processes 2007;163:33–7. Molina JM, Rhême M, Carron J, Weber L. Scr Mater 2008;58:393–9. Chu K, Liu Z, Jia C, Chen H, Liang X, Gao W, et al. J Alloys Compd 2010;490:453–8. Koltsova A, Hodaja F, Eustathopoulosa N, Dezellusb A, Plaindouxb P. Scr Mater 2003;48:351–7. Schubert T, Ciupinski L, Zielinski W, Michalski A, Weißgärber T, Kieback B. Scr Mater 2008;58:263–6. Tavangar R, Molina JM, Weber L. Scr Mater 2007;56:357–60. Zhang Y, Zhang HL, Wu JH, Wang XT. Scr Mater 2011;65:1097–100. Weber RTL. Adv Mater Res 2009;59:111–65. Weber L, Tavangar R. Scr Mater 2007;57:988–91. Ruch PW, Beffort O, Kleiner S, Weber L, Uggowitzer PJ. Compos Sci Technol 2006;66:2677–85. Abyzov A, Kidalov S, Shakhov F. J Mater Sci 2011;46:1424–38. Shen W, Shao W, Wang Q, Ma M. Fusion Eng Des 2010;85:2237–40. Yoshida K, Morigami H. Microelectron Reliab 2004;44:303–8. Liu B, Zhang Y. J Alloys Compd 2008;458:383–9. Mizuuchi K, Inoue K, Agari Y, Sugioka M, Tanaka M, Takeuchi T, et al. Composites Part B 2012;43:1445–52. Dewar B, Nicholas M, Scott PM. J Mater Sci 1976;11:1083–9. Xiao X, Sheldon BW, Konca E, Lev LC, Lukitsch MJ. Diamond Relat Mater 2009;18:1114–7. Frage N, Froumin N, Dariel MP. Acta Mater 2002;50:237–45. Lee MT, Fu MH, Wu JL, Chung CY, Lin SJ. Diamond Relat Mater 2011;20:130–3. Xia Y, Song YQ, Lin CG, Cui S, Fang ZZ. Trans Nonferrous Met Soc China 2009;19:1161–6. Yamazaki T, Suzumura A. J Mater Sci 1998;33:1379–84. Lee YK, Hwang SH, Lee JY. J Mater Sci 1993;28:1765–71.
Contents lists available at ScienceDirect
Materials Letters journal homepage: www.elsevier.com/locate/matlet
Effects of Ti addition on thermal properties of diamond/Ag–Ti composites fabricated by liquid sintering Mu-Tse Lee, Chih-Yu Chung, Chun-Ming Lin, Su-Jien Lin n Department of Materials Science and Engineering, National Tsing Hua University, Hsinchu 300, Taiwan
art ic l e i nf o
a b s t r a c t
Article history: Received 13 September 2013 Accepted 1 November 2013 Available online 9 November 2013
Diamond/Ag–Ti composites were fabricated by a low-cost vacuum liquid sintering technique and the effects of Ti addition on the thermal properties of the composites were studied. The results indicate that the optimal quantity of added Ti is 3 at%. Adding less than 3 at% Ti resulted in poor wettability, while adding more than 3 at% Ti resulted in excessive formation of TiC. Both reduced thermal conductivity. A composite comprising 60 vol% diamond/Ag–3at%Ti resulted in a maximum thermal conductivity of 836 W m 1 K 1 with a coefficient of thermal expansion of 5.6 10 6 K 1 . These composites are excellent candidates for the thermal management of integrated electronic devices. & 2013 Published by Elsevier B.V.
Keywords: Microstructure Interfaces Thermal properties Composite materials
1. Introduction Thermal management is an important issue in the development of electronic devices with high power density requirements [1,2]. The efficient removal of heat from high density integrated circuitry depends upon two essential factors: thermal conductivity (TC) and the coefficient of thermal expansion (CTE). The TC of heat spreading/sinking materials must be as high as possible and the CTE must equal that of the materials of which the semiconductors are composed, such as Si, InP, and GaAs (CTE range 4–7 10 6 K 1) [3,4]. Diamond-based metal matrix composites (MMCs), such as diamond/Cu, diamond/Al, and diamond/Ag, have attracted considerable attention as heat-spreading materials [3,5–11] due to their high TC and CTE, which can be tuned to match that of the semiconductors. A challenge associated with diamond-based MMCs is the cost of the equipment required for processes such as metal infiltration [7,9,12], hot pressing [13], hot isotactic pressing [14], and spark plasma sintering (SPS) [4,15,16]. Eliminating the need for expensive equipment is essential for the mass production of high TC diamond-based MMCs. Another challenge is the poor wettability between the metal matrix and diamond. The addition of carbide-forming metal into the matrix, such as Cr, B, Zr, or Ti [5,10,17,18], can improve the wettability [2,6,13]. Ensuring high TC requires that the carbide interlayer be continuous and thin [2,18]. However, few studies have investigated the quantity effect of carbide-forming element. This paper
n
Corresponding author. Tel.: þ 886 3571 5131x342620; fax: þ 886 3572 2366. E-mail address: [email protected] (S.-J. Lin).
0167-577X/$ - see front matter & 2013 Published by Elsevier B.V. http://dx.doi.org/10.1016/j.matlet.2013.11.001
presents a low-cost cold pressing and vacuum liquid sintering process to fabricate the diamond/Ag–Ti composites and the effects of Ti addition on the thermal properties of the composites were studied. 2. Experimental Silver powder (99.99 wt% in purity, Agpro) with an average size of 5 μm and Ti powder (99.9 wt% in purity, Unionward) with an average size of 35 μm and diamond particles (YK-9E with the thermal conductivity of 1800 W m 1 K 1, Fine Abrasives, Taiwan) with an average size of 300 μm were mechanically mixed and cold-pressed at 700 MPa for 20 min. The compacted composite was then sintered in a vacuum (base pressure ¼4.5 10 2 Torr) with 30 sccm H2 at 1278 K for 30 min. The microstructure was observed by a scanning electron microscope (SEM; JEOL-5410, Japan). The crystal structures were identified by an X-ray diffractometer (XRD, Rigaku, Japan) using Cu Kα radiation with the operating voltage and current of 30 kV and 20 mA, respectively. Thermal diffusivity (D) and specific heat (C) were measured using a laser flash analyzer (Netzsch LFA 447, Germany), while thermal conductivity (K) was determined according to the relationship K ¼D ρ C, where ρ is the density of the composite. The theoretical densities of pure silver (10.5 g cm 3), pure titanium (4.5 g cm 3) and diamond (3.52 g cm 3) were used to calculate the relative density of samples. In the experiment, the densities of the composites were measured according to Archimedes’ law and compared with theoretical densities to obtain the relative densities. The coefficients of thermal expansion (CTEs) were measured using a thermal analysis apparatus (TA Instruments, TMA 2940, U.S.A.)
M.-T. Lee et al. / Materials Letters 116 (2014) 212–214
at a heating rate of 10 K min 1 from 298 K to 423 K. Focused ion beam (FIB, FEI-Nova 200) technology was used for the preparation of samples prior to observation under transmission electron microscopy (TEM) was performed using a JEOL JEM-2100 electron microscope operated at 200 kV. 3. Results and discussion Fig. 1 presents surface SEM images of the 60 vol% diamond composites with various proportions of Ti added to the Ag matrix. We have studied 50 vol%, 60 vol% and 70 vol% diamond composites, and we found that 60 vol% exhibit the highest TC. At 1 at% Ti, the composite presented a number of voids, indicating poor wettability due to insufficient Ti content. The composites produced with 3 and 5 at% Ti both presented good wetting behavior to the surface of the diamonds. This wetting behavior of the Ti promoted the wettability of the Ag to the diamond [5,19]. These results are in line with those of previous studies [19]. Fig. 2 presents the X-ray diffraction spectra of composites produced with 60 vol% diamond within an Ag–3 at% Ti matrix. The diffraction peaks in Fig. 2a can be attributed to diamond, Ag, TiAg, and TiC, Ag and TiAg peaks nearly overlap [17], indicating that the lattice constants of Ag and TiAg are similar. XRD analysis confirms the successful fabrication of diamond/Ag–Ti composites without impurities. These results also confirm the formation of TiC during the sintering process following the addition of Ti to the Ag matrix. Fig. 2b presents a backscattered electron image (BEI) of the same sample as well as element mapping by energy dispersive spectroscopy (EDS), showing Ti-rich areas on the diamond sites. These results show that most of the Ti appeared on the surface of the diamond particles, indicating the preference of Ti for diffusion bonding with diamond, rather than with the Ag matrix.
213
Fig. 3 presents the curves representing Ti content within the matrix versus TC and the relative density of the diamond/Ag–Ti composites. The relative densities of the composites increased with an increase in Ti content from 1 at% up to 3 at% Ti, remaining relatively high ( 498.4%) until 5 at%. The presence of pores reduced densification to only 97.4% when the Ti content was 1 at%. This phenomenon can be attributed to the relatively low Ti content, causing inefficient wetting of the diamond interfacial area (see Fig. 1). The reduction in relative density subsequently reduced the TC of the composites [14,20]. The CTE measurements of diamond/Ag–Ti composites were 6.9, 6.4, 5.6, 5.6, and 5.7 10 6 K 1 for 1, 2, 3, 4, and 5 at% Ti additions, respectively. The CTEs of the diamond/Ag–Ti composites decreased with an increase in Ti content and remained at 5.6 10 6 K 1 when the Ti content was 3 at% or higher. These results indicate that 3 at% Ti is sufficient to improve wettability and bonding between the diamond reinforcement and Ag matrix. Fig. 3 presents the TC values of the diamond/Ag–Ti composites (578–836 W m 1 K 1). These considerably high values demonstrate the potential of the proposed vacuum liquid sintering technique for the fabrication of diamond/Ag–Ti composites. Fig. 3 also illustrates an increase in TC for composites with Ti content up to 3 at%, that followed by a decrease for composites with Ti content above 3 at%. These figures illustrate the trade-off between wettability and total TC in the diamond/Ag–Ti system. The wettability of the diamond/Ag interface increased with an increase in Ti content from 1 to 5 at% Ti (Fig. 1). However, the TC of the composite decreased when more than 3 at% Ti was added, due to an increase in TiC with low TC (27 W m 1 K 1) [21]. The TC of the diamond/Ag–3 at% Ti composite was as high as 836 W m 1 K 1, which similar that of diamond/Ag composites fabricated by spark plasma sintering (SPS) [16].
Fig. 1. SEM surface images of the 60 vol% diamond/Ag composite sintered at 1278 K with different Ti composition in the matrix from 1 at%, 3 at% and 5 at%.
Fig. 2. (a) X-ray diffraction pattern, (b) the BEI surface image and its corresponding EDS element mappings of Ag, C and Ti for the 60 vol% diamond/Ag–3 at% Ti composite.
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M.-T. Lee et al. / Materials Letters 116 (2014) 212–214
patterns matched the standards of titanium carbide (TiC), as shown in the insert of Fig. 4a. The formation of TiC on the surface of the diamond particles provides evidence of the enhanced wettability of the diamond/Ag–Ti composites.
4. Summary
Fig. 3. Ti content vs. TC and relative density of 60 vol% diamond/Ag–Ti composite.
Diamond/Ag–Ti composites were fabricated by a low-cost cold pressing followed by vacuum liquid sintering and the effects of Ti addition on the thermal properties of the composites were studied. The addition of Ti to the Ag matrix increased the wettability and adhesion of Ag to the surface of the diamond particles through an interface reaction, resulting in the formation of Ti-rich layer. This improvement in wettability improved the density of the resulting materials and subsequently enhanced the thermal properties of the composite. The optimal quantity of added Ti is 3 at%. Adding less than 3 at% Ti resulted in poor wettability, while adding more than 3 at% Ti resulted in excessive formation of TiC. Both reduced thermal conductivity. A composite comprising 60 vol% diamond/Ag–3 at%Ti resulted in a maximum thermal conductivity of 836 W m 1 K 1 with a coefficient of thermal expansion of 5.6 10 6 K 1. These composites are excellent candidates for the thermal management of integrated electronic devices.
Acknowledgement The authors would like to thank the National Science Council, Taiwan, R.O.C. for the support of this research through the project No: NSC-102–2221-E-007-046-MY3. References
Fig. 4. TEM bright field image (insert is the selected area diffraction pattern of Tirich area) and its corresponding element mappings of C, Ag and Ti of the diamond/ Ag interface cut from the surface of 60 vol% diamond/Ag–5 at% Ti composite.
[1] [2] [3] [4] [5]
According to the above results, we can conclude that the optimal Ti content addition is 3 at% for the 300 μm diamond/ Ag–Ti composites. Adding less than 3 at% Ti resulted in poor wettability, while adding more than 3 at% Ti resulted in excessive formation of TiC. Both reduced thermal conductivity. Improving the wettability resulted in higher relative density ( 498.4%) and lower CTE ( 5.6 10 6 K 1). However, the formation of excessive TiC reduced the TC, due to the low TC of TiC. The interfacial structure and elemental distribution were further characterized by TEM mapping to check the TiC peaks and Ti distribution, as shown in Fig. 4. Three distinct elemental distributions were observed: diamond, a Ti-rich layer, and the Ag– Ti region. The Ti-rich layer was approximately 1000 nm in thickness and contained a layer (approximately 150 nm in thickness) containing both Ag and Ti. This Ti-rich layer was produced by diffusion and its presence is consistent with the observations of previous studies [22,23]. The major constituents of the Ti-rich layer were identified by TEM. Selected area diffraction (SAD)
[6] [7] [8] [9] [10] [11] [12] [13] [14] [15] [16] [17] [18] [19] [20] [21] [22] [23]
Zweben C. J Metal 1998;50:47–51. Zweben C. Adv Mater Processes 2007;163:33–7. Molina JM, Rhême M, Carron J, Weber L. Scr Mater 2008;58:393–9. Chu K, Liu Z, Jia C, Chen H, Liang X, Gao W, et al. J Alloys Compd 2010;490:453–8. Koltsova A, Hodaja F, Eustathopoulosa N, Dezellusb A, Plaindouxb P. Scr Mater 2003;48:351–7. Schubert T, Ciupinski L, Zielinski W, Michalski A, Weißgärber T, Kieback B. Scr Mater 2008;58:263–6. Tavangar R, Molina JM, Weber L. Scr Mater 2007;56:357–60. Zhang Y, Zhang HL, Wu JH, Wang XT. Scr Mater 2011;65:1097–100. Weber RTL. Adv Mater Res 2009;59:111–65. Weber L, Tavangar R. Scr Mater 2007;57:988–91. Ruch PW, Beffort O, Kleiner S, Weber L, Uggowitzer PJ. Compos Sci Technol 2006;66:2677–85. Abyzov A, Kidalov S, Shakhov F. J Mater Sci 2011;46:1424–38. Shen W, Shao W, Wang Q, Ma M. Fusion Eng Des 2010;85:2237–40. Yoshida K, Morigami H. Microelectron Reliab 2004;44:303–8. Liu B, Zhang Y. J Alloys Compd 2008;458:383–9. Mizuuchi K, Inoue K, Agari Y, Sugioka M, Tanaka M, Takeuchi T, et al. Composites Part B 2012;43:1445–52. Dewar B, Nicholas M, Scott PM. J Mater Sci 1976;11:1083–9. Xiao X, Sheldon BW, Konca E, Lev LC, Lukitsch MJ. Diamond Relat Mater 2009;18:1114–7. Frage N, Froumin N, Dariel MP. Acta Mater 2002;50:237–45. Lee MT, Fu MH, Wu JL, Chung CY, Lin SJ. Diamond Relat Mater 2011;20:130–3. Xia Y, Song YQ, Lin CG, Cui S, Fang ZZ. Trans Nonferrous Met Soc China 2009;19:1161–6. Yamazaki T, Suzumura A. J Mater Sci 1998;33:1379–84. Lee YK, Hwang SH, Lee JY. J Mater Sci 1993;28:1765–71.