It is important, for electronic application, to decrease the melting point of Sn-5Sb solder alloy because it is relatively high as compared with the most popular eutectic Pb-Sn solder alloy. Adding Au or Ag can decrea...It is important, for electronic application, to decrease the melting point of Sn-5Sb solder alloy because it is relatively high as compared with the most popular eutectic Pb-Sn solder alloy. Adding Au or Ag can decrease the onset melting temperature （233℃） of this alloy to 203,5℃ and 216℃, respectively. The results indicate that the Sn-5Sb-i.5Au alloy has very good ultimate tensile strength （UTS）, ductility, and fusion heat, which are better than both those of the Sn-5Sb-3.SAg and Sn-5Sb alloys. The formation of intermetallic compounds （IMCs） AuSn4 and Ag3Sn enhanced the SbSn precipitates in the solidification microstructure microstructure stability, while retained the formation of thus significantly improved the strength and ductility For all alloys, both UTS and yield stress （σy） increase with increasing strain rate and decrease with increasing temperature in tensile tests, but changes of ductility are generally small with inconsistent trends.展开更多
The growth rule of the interfacial intermetallic compound （IMC） and the degradation of shear strength of Sn-0.SAg-0.5Cu-2.0Bi-0.05Ni （SACBN）/Cu solder joints were investigated in comparison with Sn-3.0Ag-0.5Cu （S...The growth rule of the interfacial intermetallic compound （IMC） and the degradation of shear strength of Sn-0.SAg-0.5Cu-2.0Bi-0.05Ni （SACBN）/Cu solder joints were investigated in comparison with Sn-3.0Ag-0.5Cu （SAC305）/ Cu solder joints aging at 373, 403, and 438 K. The results show that （Cul-x,Nix）6Sn5 phase forms between the SACBN solder and Cu substrate during soldering. The interracial IMC thickens constantly with the aging time increasing, and the higher the aging temperature, the faster the IMC layer grows. Compared with the SAC305/Cu couple, the SACBN/Cu couple exhibits a lower layer growth coefficient. The activation energies of IMC growth for SACBN/Cu and SAC305/Cu couples are 111.70 and 82.35 kJ/mol, respectively. In general, the shear strength of aged solder joints declines continuously. However, SACBN/Cu solder joints exhibit a better shear strength than SAC305/Cu solder joints.展开更多
The solder joint strength of Pb/Sn soldering aluminum with electroless layer Sn/Bi and Cu was studied. The results show that the joint shear strength of electroless Sn/Bi on aluminum surface is lower than that of Cu. ...The solder joint strength of Pb/Sn soldering aluminum with electroless layer Sn/Bi and Cu was studied. The results show that the joint shear strength of electroless Sn/Bi on aluminum surface is lower than that of Cu. A Pb-riched region with porosity is formed in region of soldering fillet with electroless Sn/Bi. Both the electroless Sn/Bi layer and Pb-riched layer become thicker, which are the reasons why the shear strength of the solder joint with electroless Sn/Bi on aluminum surface is lower than that of electroless Cu, and the higher the thickness of the electroless Sn/Bi layer is, the lower the shear strength of solder joint is.展开更多
The bond strength of the Sn based ternary active solders,Sn-5Ti with various contents of Ag,Cu,In, Ni or AI on sialon ceramic was investigated by the ceramic/ceramic joint joining.The bond strength of Sn-STi (about 80...The bond strength of the Sn based ternary active solders,Sn-5Ti with various contents of Ag,Cu,In, Ni or AI on sialon ceramic was investigated by the ceramic/ceramic joint joining.The bond strength of Sn-STi (about 80 MPa) may increase to 90-100 MPa by small addition of Ag or Cu (about 5-10%).A little Ni (about 1-3%) in the solder is slightly beneficial,but too more Ni (more than 5%) is harmful.Small addition of In is trivial,but too more In is detrimental.On the other hand,small addi- tion of AI in the active solder decreases greatly the bond strength of the solder,therefore it is very harmful.In discussion,three suggestions for selection of the third element to increase the bond strength of the soft solders on ceramic,i.e.with a high surface energy,benefiting to wetting on ce- ramic and strengthening the soft solder itself,have been made.展开更多
In this work, the wettability, aging and shear properties of a new type of lead-free solder paste Sn-01Ag-Q5Cu ＋ BiNi （SACBNQ7） was investigated by conducting a series of comparison experiments with SAC305 and SAC...In this work, the wettability, aging and shear properties of a new type of lead-free solder paste Sn-01Ag-Q5Cu ＋ BiNi （SACBNQ7） was investigated by conducting a series of comparison experiments with SAC305 and SAC0307 solder paste. The results show that wettability of SACBNQ1 is almost equal to SAC3Q5,and better than that of SACQ3Q1 solder paste. The thickness of intermetallic compound （IMC） layer in SACBNQl/Cu is lower than that o f other two types o f solder joint after aging. And Cu3Sn layer of SACBNQl/Cu is thinner than that of SAC3Q5 and SAC0307. In addition, the SACBNQ7 solder joints perform the best shear strength among these three types of solder pastes.展开更多
文摘It is important, for electronic application, to decrease the melting point of Sn-5Sb solder alloy because it is relatively high as compared with the most popular eutectic Pb-Sn solder alloy. Adding Au or Ag can decrease the onset melting temperature （233℃） of this alloy to 203,5℃ and 216℃, respectively. The results indicate that the Sn-5Sb-i.5Au alloy has very good ultimate tensile strength （UTS）, ductility, and fusion heat, which are better than both those of the Sn-5Sb-3.SAg and Sn-5Sb alloys. The formation of intermetallic compounds （IMCs） AuSn4 and Ag3Sn enhanced the SbSn precipitates in the solidification microstructure microstructure stability, while retained the formation of thus significantly improved the strength and ductility For all alloys, both UTS and yield stress （σy） increase with increasing strain rate and decrease with increasing temperature in tensile tests, but changes of ductility are generally small with inconsistent trends.
基金financially supported by the National Natural Science Foundation of China(No.U0734006)Shenzhen Tongfang Electronic New Material Co.,Ltd
文摘The growth rule of the interfacial intermetallic compound （IMC） and the degradation of shear strength of Sn-0.SAg-0.5Cu-2.0Bi-0.05Ni （SACBN）/Cu solder joints were investigated in comparison with Sn-3.0Ag-0.5Cu （SAC305）/ Cu solder joints aging at 373, 403, and 438 K. The results show that （Cul-x,Nix）6Sn5 phase forms between the SACBN solder and Cu substrate during soldering. The interracial IMC thickens constantly with the aging time increasing, and the higher the aging temperature, the faster the IMC layer grows. Compared with the SAC305/Cu couple, the SACBN/Cu couple exhibits a lower layer growth coefficient. The activation energies of IMC growth for SACBN/Cu and SAC305/Cu couples are 111.70 and 82.35 kJ/mol, respectively. In general, the shear strength of aged solder joints declines continuously. However, SACBN/Cu solder joints exhibit a better shear strength than SAC305/Cu solder joints.
文摘The solder joint strength of Pb/Sn soldering aluminum with electroless layer Sn/Bi and Cu was studied. The results show that the joint shear strength of electroless Sn/Bi on aluminum surface is lower than that of Cu. A Pb-riched region with porosity is formed in region of soldering fillet with electroless Sn/Bi. Both the electroless Sn/Bi layer and Pb-riched layer become thicker, which are the reasons why the shear strength of the solder joint with electroless Sn/Bi on aluminum surface is lower than that of electroless Cu, and the higher the thickness of the electroless Sn/Bi layer is, the lower the shear strength of solder joint is.
文摘The bond strength of the Sn based ternary active solders,Sn-5Ti with various contents of Ag,Cu,In, Ni or AI on sialon ceramic was investigated by the ceramic/ceramic joint joining.The bond strength of Sn-STi (about 80 MPa) may increase to 90-100 MPa by small addition of Ag or Cu (about 5-10%).A little Ni (about 1-3%) in the solder is slightly beneficial,but too more Ni (more than 5%) is harmful.Small addition of In is trivial,but too more In is detrimental.On the other hand,small addi- tion of AI in the active solder decreases greatly the bond strength of the solder,therefore it is very harmful.In discussion,three suggestions for selection of the third element to increase the bond strength of the soft solders on ceramic,i.e.with a high surface energy,benefiting to wetting on ce- ramic and strengthening the soft solder itself,have been made.
基金supported by National Natural Science Foundation of China(Grant No.51174069)
文摘In this work, the wettability, aging and shear properties of a new type of lead-free solder paste Sn-01Ag-Q5Cu ＋ BiNi （SACBNQ7） was investigated by conducting a series of comparison experiments with SAC305 and SAC0307 solder paste. The results show that wettability of SACBNQ1 is almost equal to SAC3Q5,and better than that of SACQ3Q1 solder paste. The thickness of intermetallic compound （IMC） layer in SACBNQl/Cu is lower than that o f other two types o f solder joint after aging. And Cu3Sn layer of SACBNQl/Cu is thinner than that of SAC3Q5 and SAC0307. In addition, the SACBNQ7 solder joints perform the best shear strength among these three types of solder pastes.
