Properties Of Solder Research Articles

Evaluation of the microstructure, thermal, and mechanical characteristics of Sn-9Zn reinforced with Ni and ZrO2 nanoparticles via vacuum melting process

The impact of minor additions of nickel and ZrO2 nanoparticles to eutectic Sn-9wt%Zn (SZ) prepared by vacuum melting technique was investigated. The morphologies and microstructures were carried out using an optical microscope (OM) and field emission scanning electron microscope technique (FESEM) escorted by energy dispersive x-ray spectrometry (EDX). The phase structure of the specimens was confirmed by an x-ray diffractometer (XRD). The results obtained demonstrate that small Ni addition causes a major grain refinement of β-Sn, due to the formation of the fine intermetallic compounds Ni5Zn21 and Sn3Ni4Zn3 phases and refines the formation of α- Zn lamellar phase. The melting temperature of the recently discovered solder alloys was lower than that of the eutectic Sn-Zn solders (∆Tm ∼ 28 °C) as a result of the preparation technique and the incorporation of Ni and ZrO2 nanoparticles. The tensile test showed enhanced the mechanical properties of SZ solder as a result of the addition of third elements. The experimental results showed that of all the alloys under investigation, the SZN903 alloy had the greatest UTS and YS values. The enhanced strength of the SZ-ZrO2 alloy defended the results of σ UTS and increased the stress exponent parameters, n, by ∼20%. All solders had an activation energy Q that measured between ∼35.62 kJ mol−1 to ∼58.12 kJ mol−1 which comparable to the pipe-diffusion mechanism.

Microstructure and mechanical properties of Sn-xGa alloys and solder joints

Though Ga is a promising addition used in third-generation lead-free solders for harsh-environment applications, its influences on βSn structure and mechanical properties of solder alloys/joints are still unknown. This study demonstrated that Ga additions in Sn-XGa (X = 0.5, 1.0, 2.0 in wt%) can moderately refine βSn grains but render the alloys more susceptible to recrystallization during cross-section and polishing. Sn-1.0Ga shows substantially elevated yield/tensile strengths (45.1 MPa/64.9 MPa) compared with pure Sn, attributed to the strong solid-solution strengthening effect of Ga, and it also possesses good tensile ductility of >25%. Compared with pure Sn and Sn-3.0Ag-0.5Cu (SAC305) solder joints on Cu, Sn-XGa/Cu solder joints show significantly reduced dissolution of Cu substrate that benefits in suppressing the formation of primary Cu6Sn5. Among Sn-XGa/Cu, Sn-2.0Ga/Cu joint exhibits high shear strength (69.4 MPa) comparable to that of SAC305/Cu joint (70.5 MPa), owing to the Ga solid-solution strengthening and the extra second-phase strengthening from Cu9Ga4.

Effect of the addition of CeO2 nanoparticles on the microstructure and shear properties of Sn–57Bi–1Ag solder alloy

In this study, different weight fractions (0, 0.2, 0.5, 0.7, and 1.0 wt%) of cerium oxide (CeO2) nanoparticles were used to enhance the properties of Sn–58Bi–1Ag (SBA) solder alloys. As expected in the design, the CeO2 nanoparticles are diffusely distributed in the solder matrix. The microstructure evolution, growth of intermetallic compound (IMC) at the interface, and shear properties of the composite solder were systematically investigated using a scanning electron microscope (SEM) equipped with energy-dispersive X-ray spectroscopy (EDS) and electron backscatter diffraction (EBSD) probes. The results showed that adding an appropriate amount of CeO2 nanoparticles can refine the microstructure of the composite solder. Many β-Sn twin structures were observed in the SBA-0.5CeO2 and SBA-0.7CeO2 solder matrix, bringing better deformability to the β-Sn phase and improving the plasticity of the solder matrix. Moreover, with the addition of nanomaterials, there was a notable decrease in the thickness of the interfacial IMC layer of the solder/Cu joint, accompanied by a refinement in the grain size of the IMC. To our satisfaction, the addition of CeO2 nanoparticles in the appropriate proportion exhibited a remarkable enhancement in both shear strength and toughness of the composite solder alloys, working in tandem to transform the fracture mechanism from a purely brittle mode to a mixed mode of ductility and brittleness. It is indicated that the doping of CeO2 improves the reliability of SBA solder, potentially paving the way for a novel approach to particle-enhanced modification of Sn–Bi–Ag-based low-temperature solders.

To study the effect of Ni particles on microstructures and mechanical properties of Indium-Bismuth solder alloy

In this work, Ni particles were added to the In-34Bi solder alloy to enhance the mechanical properties of solder at ambient temperature. The microstructure seems to be fingerprint-like structures similar to pearlitic structures as seen in eutectoid steel. However, in this case, InBi2bands are seen in the Indium matrix. The distribution of Nickel particles was seen in backscattered images of scanning electron macroscopic images. Mechanical properties are improved by the addition of Ni particles in In-34Bi-1Ni solder alloy. The solder alloy's hardness has improved by 36%, its 0.2% proof stress has risen by 34%, and its ultimate tensile strength has increased by 40%. Distribution of Ni particles in In-34Bi-1Ni solder alloy confirmed In2Bi and Ni2In3. The presence of Ni and Ni2In3 tends to decrease ductility from 50% to 35%. The addition of Ni particles in In-34Bi-1Ni showed significant improvements in mechanical properties.

Significant enhancement of comprehensive properties of SnBi solder through the addition of Cu@Ag core-shell particles

As a critical low-temperature lead-free solder, SnBi eutectic solder was known for its abundant lamellar structures of Bi-rich phase, which often resulted in problems such as brittleness, low electrical conductivity, and low thermal conductivity. In this study, a method was introduced to enhance the comprehensive properties of SnBi solder by adding Cu@Ag core-shell particles. Our results revealed that the modified SnBi solder exhibited significant refinement in both grain size and intragranular eutectic structures, resulting in a shift from the original brittle fracture mode to a mixed brittle and tough mode and a consequent increase in tensile strength by 21%. Moreover, the modified solder demonstrated a significant 59% increase in electrical conductivity by forming interconnected highspeed channels for electron migration. In addition, the addition of Cu@Ag core-shell particles to SnBi solder resulted in remarkable contributions of both electrons and phonons to thermal conductivity, with its value of 41.33 W m−1 K−1. Our research addressed partial property deficiencies of SnBi solder, which could be valuable in expanding its application in low temperature electronic packaging.

Effect of high-temperature aging on microstructure properties of Sn96.5%Ag3-Cu0.5% (SAC305) lead-free solder joints

The use of Sn96.5%Ag3%Cu0.5% (SAC305) as lead-free solder is increasing rapidly as an interconnection for electronic devices. Electronic devices face harsh environmental applications during the operation which can reach temperatures of 200 °C and expose soldiers. The microstructure properties of lead-free solders are highly dependent on the process and operating parameters such as salty water, moisture, and high temperature. In this study, the effects of aging (storing) the samples at high temperatures on SAC305 alloy were investigated as a function of microstructure characterization. Microstructure morphologies are evaluated regarding the growth of inter-metallic compounds IMCs (Ag3Sn and Cu6Sn5) and grain size. The scanning electron microscope (SEM) and optical microscope were used to analyze the microstructure of Sn grain morphology. Also, to investigate the elemental distribution, energy dispersive spectroscopy (EDS) was used. The results show distinct changes in the microstructure of SAC305 solder alloy due to the aging effect; the quantitative analysis of grain size and intermetallic particle support this result.

Effect of Ce on the microstructure and property of Sn0.7Cu solder

The effect of Ce multi-addition on wettability and microstructure of Sn-0.7Cu solder was investigated. The results indicated that the multi-addition of Ce could greatly improve the wettability of solder and refine the microstructure of solder matrix. The optimal property of solder was obtained when the addition of Ce reached 0.1 wt.%. With the increasing of Ce addition, black phase appeared and tend to be accumulated in the solder matrix. EDS results indicated that the composition of black phase contained varies elements including Sn, Cu, Ni, and Ce. Compared with the previous research results of solder with excessive Ce addition, no obviously Sn-Nd phase was observed while a small amount of Ga2Nd phase appeared in the solder matrix.

Investigation of Microstructure and Mechanical Properties of SAC105 Solders with Sb, In, Ni, and Bi Additions.

Low Ag lead-free Sn-Ag-Cu (SAC) solders have attracted great interest due to their good drop resistance, high welding reliability, and low melting point. However, low Ag may lead to the degradation of the mechanical properties. Micro-alloying is an effective approach to improving the properties of SAC alloys. In this paper, the effects of minor additions of Sb, In, Ni, and Bi on microstructure, thermal and mechanical properties of Sn-1 wt.%Ag-0.5 wt.%Cu (SAC105) were systematically investigated. It is found that the microstructure can be refined with intermetallic compounds (IMCs) distributed more evenly in the Sn matrix with additions of Sb, In, and Ni, which brings a combined strengthening mechanism, i.e., solid solution strengthening and precipitation strengthening, leading to the tensile strength improved of SAC105. When Ni is substituted by Bi, the tensile strength is further enhanced with a considerable tensile ductility higher than 25%, which still meets the practical demands. At the same time, the melting point is reduced, the wettability is improved, and the creep resistance is enhanced. Among all the investigated solders, SAC105-2Sb-4.4In-0.3Bi alloy possesses the optimized properties, i.e., the lowest melting point, the best wettability, and the highest creep resistance at room temperature, implying that element alloying plays a vital role in improving the performance of SAC105 solders.

Effects of TiO2, CuO, and SiO2 nanoparticles addition on the microstructure and mechanical properties of Al-10 wt% Zn alloy

This paper presents the effects of adding TiO2, CuO, and SiO2 (1 wt%) nanoparticles on the microstructure and mechanical properties of Al-10 wt% Zn alloy. A set of composite alloys was produced by incorporating SiO2, CuO, and TiO2 nanoparticles to the Al-10 wt% Zn alloy. Optical microscope (OM), scanning electron microscope (SEM) fitted with an Energy Dispersive Spectroscope (EDS), and X-ray diffraction (XRD) were used to investigate the microstructure of these alloys. The mechanical properties of the composite solders were assessed using the Vickers hardness tests. After a solution heat treatment at 500 K for 2 h, samples were immediately aged at 373 to 473 K for 2 h, followed by water quenching at 300 K. The experimental data indicated that Al-10 wt% Zn-1wt% SiO2 samples had the highest hardness values among all investigated composite alloys. The calculated porosity percentages of the composite alloys revealed that the Al-10 wt% Zn-1 wt% SiO2 samples had the lowest percentage. This finding can be attributed to the fact that these samples demonstrated the highest hardness values. The hardness of all composite alloys decreased with increasing the aging temperature with anomalous behavior at 443 K, where they had abnormally high values. The observed differences in the mean crystallite size, lattice strain, and dislocation density of the composite alloys, calculated from XRD data with increasing aging temperature, are attributed to the precipitation in Al-Zn alloys. The calculated values of the stress exponent and activation energy of composite alloys may be associated with grain boundary diffusion (GBD) as the dominant operating mechanism.

Effect of Carbon Nanotubes on the Mechanical, Thermal, and Electrical Properties of Tin-Based Lead-Free Solders: A Review

Carbon nanotubes (CNTs) are being applied with increasing frequency for advanced soldering. They have excellent mechanical, electrical, and thermal properties and are primarily used to reinforce lead-free solders. This paper discusses the strengthening mechanism of CNTs, introduces the preparation methods of CNT composite solders, and focuses on the review of tin-based lead-free solders reinforced with unmodified CNTs and metal-modified CNTs. The addition of CNTs can effectively improve the ultimate tensile strength, microhardness, shear strength, and creep resistance of the solder. However, the practical application of CNT composite solders has been a challenge for researchers for decades. The most significant issue is uniform dispersion due to the large density and surface differences between CNTs and solders. Other concerns are the structural integrity of CNTs and their limited addition amount, solder wettability, and interfacial bonding. CNT composite solders can only be widely used in a real sense when these challenges are properly addressed and overcome. At present, there is a lack of comprehensive reviews covering the structure, the strengthening mechanism, the preparation method of CNT composite solders, and the influence of CNT types on their strengthening effects. Therefore, this paper aims to fill this gap and contribute to solving the problems faced by the application of CNTs in solder. Future work is expected to focus on improving the dispersion and bonding of CNTs and optimizing the preparation method.

Effects of Near-amorphous multiphase intermetallic compound particles on the microstructure and mechanical properties of SnBi solders

Effects of Near-amorphous multiphase intermetallic compound particles on the microstructure and mechanical properties of SnBi solders

Investigation of microstructure and mechanical properties of lead free composite solder containing cobalt microparticles produced by accumulative roll bonding

Investigation of microstructure and mechanical properties of lead free composite solder containing cobalt microparticles produced by accumulative roll bonding

Effect of Graphene Nanosheets on the Microstructure and Mechanical Properties of Sn-20Bi Solder.

The application of Sn-Bi series solder is limited due to the brittleness of Bi phase. Sn-20Bi solder with less Bi element content has great research prospects, but it needs modification to make it a substitute for traditional Sn-Pb solder. In this article, we mixed graphene nanosheets with nanometer Sn powder by means of ultrasonic oscillation, and Sn-20Bi-qGNS (q = 0.01, 0.02, 0.04, 0.06, and 0.1 wt.%) solder alloys were prepared by the melt-casting method. The effects of graphene nanosheets (GNSs) on the microstructure, physical properties, mechanical properties, and corrosion resistance of solder alloys were investigated. Scanning electron microscopy, energy dispersive spectroscopy, X-ray diffraction, and X-ray photoelectron spectroscopy were used to determine the microstructural morphology and composition. The results showed that the melting point, density, and wettability of the solder decreased slightly with the addition of GNSs. The addition of GNSs as a second phase refined the solder structure and improved the tensile strength of the molten Sn-20Bi composite solder to 99.6 MPa, while elongation decreased with the addition of GNSs. Furthermore, GNSs prevented the MC Sn-20Bi-qGNSs/Cu intermetallic compound layers' growth by interfering with atomic diffusion and grain boundary movement. In addition, the addition of 0.02 wt.% GNSs enhanced the shear strength of MC Sn-20Bi solder joints to 46.3 MPa. The electrochemical experimental results show that the surface corrosion products of MC Sn-20Bi-qGNSs under 3.5% NaCl solution were Sn3O(OH)2Cl2, with MC Sn-20Bi-0.01GNSs exhibiting the best corrosion resistance.

An insight into dynamic properties of SAC305 lead-free solder under high strain rates and high temperatures

The development of high density and high integration of electronic chips puts forward stricter requirements on electronic packaging structures. Under the premise of lead-free rules, Sn-3.0Ag-0.5Cu (SAC305) has developed into a competitive solder material. However, the reliability of its mechanical properties has been attracting much attentions especially under extreme conditions. In this paper, the high-strain rate experiments are performed by a split-Hopkinson pressure bar (SHPB) to realize different plastic strain rate, while the high temperature environment is achieved by incorporating a heating furnace. By combining these two devices, the dynamic responses of solder specimens can be measured in the strain rate range from 833 s−1 to 1961 s−1 and the temperature conditions of 70 °C and 120 °C. It is worth noting that as a typical strain-rate hardening process, the maximum stress undergoes an initial ascending stage as the applied strain rate increases. Nevertheless, the hardening process is followed by a descending stage to indicate a softening process of maximum stress due to a further temperature increase during the rapid material deformation at higher strain rates. To gain a further insight into this maximum stress transition, the microstructure characterizations of the impacted solder specimens are carried out by a scanning electron microscope (SEM). It is found that the β-Sn phases and eutectic phases appear to experience refinement and then coarsen as the plastic strain rate continues to increase. A finite element (FE) model is created in the commercial nonlinear FE software ABAQUS/Explicit by considering all the experimental details. Since none of the existing material models in the material library is available for such a maximum stress transition with different ranges of strain rate, the mechanical properties of solder material are emphasized by proposing an improved Johnson-Cook model which can be readily utilized in the numerical evaluations of packaging structures under extremely high strain-rate conditions.

Porosity effect on the mechanical properties of nano-silver solder

Nano-silver has the characteristics of low-temperature sintering and high-temperature service, which can reduce the thermal stress in the packaging process. Because of the high melting point and good high-temperature mechanical properties, silver is widely used in high-temperature packaging and connection fields. Sintered nano-silver has a porous structure on the microscopic level, it is necessary to study the mechanical properties of nano-silver with porosity. In this paper, we proposed a method for finite element modeling of porous nano-silver. Finite element analysis and nanoindentation test were used to investigate the Young’s modulus of nano-silver. At the same time, and the quadratic equation of porosity and Young’s modulus was fitted, and it was verified by Ramakrishnan model and nanoindentation results. These results show that the Young’s modulus of nano-silver decreases with the increase of internal porosity, and the Young’s modulus and porosity show a quadratic function correlation. As the porosity increases, the Young’s modulus of nano-silver decreases at a slower rate. The modeling method presented in this paper can well predict the Young’s modulus of nano-silver.

AURUBIS CuZn0.5

Abstract Aurubis CuZn0.5 is a copper alloy deoxidized by the addition of zinc. It has good electrical conductivity (≥ 82% IACS), and higher strength as compared to pure copper. This alloy has very good welding and soldering properties because it is largely insensitive to hydrogen embrittlement. This datasheet provides information on composition, physical properties, hardness, elasticity, tensile properties, and bend strength. It also includes information on corrosion resistance as well as forming and joining. Filing Code: Cu-938. Producer or source: Aurubis AG.

Microstructure evolution and thermal, wetting, mechanical properties of SiC nanowires reinforced SAC105 composite solder

In this paper, SiC nanowires (NWs) were added to the SAC105 solder as an enhancement agent. By mechanical stirring, the Sn1.0Ag0.5Cu (SAC105)-xSiC (x = 0, 0.2, 0.4, 0.6, 0.8, 1.0 wt%) solders were prepared and served as samples to investigate the thermal properties, wettability, microstructure, interfacial microstructure, and mechanical properties. It was found that the addition of 0.4% SiC NWs allowed a substantial increase in the spreading area. The Cu6Sn5 IMC and Ag3Sn IMC, and β-Sn grains were significantly refined within the SAC105-0.6SiC solder matrix. Meanwhile, the interfacial morphology became much flatter, and the thickness was minimized. Due to the refinement of Ag3Sn IMC and the reduction of the interfacial thickness, the mechanical properties of the composite solder were unsurprisingly improved. These were well demonstrated by the deeper and smaller dimples derived from the fracture surface. In addition, the mechanisms of microstructure refinement and enhancement of mechanical properties were revealed from the aspects of dispersion, adsorption, and pinning effect of SiC NWs. The deterioration of solder properties due to the agglomeration of SiC NWs was also well discussed.

KME Cu-PHC (C10300)

Abstract KME Cu-PHC is a phosphorus-deoxidized copper that contains a minimum of 99.95% copper and low residual phosphorus. It has very high thermal and electrical conductivity, and good welding and soldering properties. The electrical conductivity of KME Cu-PHC is higher than that of Cu-HCP. This datasheet provides information on composition, physical properties, hardness, elasticity, and tensile properties. It also includes information on corrosion resistance as well as forming, heat treating, and joining. Filing Code: Cu-937. Producer or source: KME Germany GmbH.

Microstructure and properties of a novel SnSbAgNi solder

Microstructure and properties of a novel SnSbAgNi solder

Effect of Al2O3 Nanoparticle Addition on the Microstructure, Mechanical, Thermal, and Electrical Properties of Melt-Spun SAC355 Lead-Free Solder for Electronic Packaging

Effect of Al2O3 Nanoparticle Addition on the Microstructure, Mechanical, Thermal, and Electrical Properties of Melt-Spun SAC355 Lead-Free Solder for Electronic Packaging