共查询到9条相似文献,搜索用时 15 毫秒
1.
Effect of SiC Nanoparticle Additions on Microstructure and Microhardness of Sn-Ag-Cu Solder Alloy 总被引:1,自引:0,他引:1
In this work, lead-free composite solders were produced by mechanically mixing nominal 20 nm moissanite SiC particles with
Sn-3.8Ag-0.7Cu solder paste. The effects of the amount of SiC addition on the melting behavior, microstructure, and microhardness
of as-solidified composite solders were systematically investigated. In comparison with solder without the addition of SiC
nanoparticles, the subgrain of β-Sn, the intermetallic compounds (IMCs) average grain size and distance decreased significantly
in the composite solder matrix. This was possibly ascribed to the strong adsorption effect and high surface free energy of
the SiC nanoparticles. Our results showed that 0.05 wt.% addition of SiC nanoparticles could improve the microhardness by
44% compared with the noncomposite and that the average grain size and distance changed from 0.5 μm to 0.2 μm and from 0.6 μm to 0.32 μm, respectively. The refined IMCs, acting as a strengthening phase in the solder matrix, enhanced the microhardness of the
composite solders, in good agreement with the prediction of the classic theory of dispersion strengthening. 相似文献
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3.
The effect of soldering process variables on the microstructure and mechanical properties of eutectic Sn-Ag/Cu solder joints 总被引:2,自引:0,他引:2
Wenge Yang Lawrence E. Felton Robert W. Messler 《Journal of Electronic Materials》1995,24(10):1465-1472
Fundamental understanding of the relationship among process, microstructure, and mechanical properties is essential to solder
alloy design, soldering process development, and joint reliability prediction and optimization. This research focused on the
process-structure-property relationship in eutectic Sn-Ag/Cu solder joints. As a Pb-free alternative, eutectic Sn-Ag solder
offers enhanced mechanical properties, good wettability on Cu and Cu alloys, and the potential for a broader range of application
compared to eutectic Sn-Pb solder. The relationship between soldering process parameters (soldering temperature, reflow time,
and cooling rate) and joint microstructure was studied systemati-cally. Microhardness, tensile shear strength, and shear creep
strength were measured and the relationship between the joint microstructures and mechani-cal properties was determined. Based
on these results, low soldering tempera-tures, fast cooling rates, and short reflow times are suggested for producing joints
with the best shear strength, ductility, and creep resistance. 相似文献
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5.
液氩冷却对316L激光金属直接成形零件组织和显微硬度的影响 总被引:1,自引:4,他引:1
在激光金属直接成形过程中,为了使熔池在凝固时始终保持合理的温度梯度从而使成形件内部柱状晶组织自基板起从下到上延续生长,在成形316 L实体墙过程中采用液氩喷射冷却的方法降低成形件的温度;分析了液氩喷射冷却对实体墙金相组织和显微硬度的影响。结果显示,采用液氩喷射冷却能有效缓解激光金属直接成形过程中成形件内部的热积累现象,使柱状晶组织在实体墙内部从基板开始从下到上延续生长,一次枝晶间距最大处约为12μm,并且提高了实体墙零件的显微硬度值。 相似文献
6.
设计并采用激光熔炼工艺制备出镍基固溶体γ增韧的Mo_2Ni_3Si三元金属硅化物合金。差式扫描量热分析(DSC)及高温金相实验表明,该合金共晶温度约1287℃,液相线温度约1355℃。研究了该Mo_2Ni_3Si合金在炉冷、水冷及激光表面熔凝条件下的凝固组织。结果表明,在炉冷及水冷条件下,随着凝固冷却速度的提高,合金中Mo_2Ni_3Si初生枝晶体积分数降低、二次枝晶臂间距减小,但激光表面快速熔凝合金中Mo_2Ni_3Si初生枝晶体积分数急剧增加(62%)。激光表面快速熔凝γ/Mo_2Ni_3Si合金由于组织细小,且基体γ相被Mo及Si元素过饱和固溶,具有最优异的力学性能(显微硬度600HV);炉冷Mo_2Ni_3Si合金凝固组织初生枝晶上分布着许多显微裂纹,且显微组织为粗大的二相组织,力学性能较差。 相似文献
7.
Chen Wei Yongchang Liu Zhiming Gao Jingbo Wan Changsheng Ma 《Journal of Electronic Materials》2009,38(2):345-350
The structural stability of Sn-3.7wt.%Ag-0.9wt.%Zn-1wt.%In solder was explored by thermal aging at 473 K. According to the
microstructural observations, the high cooling rate (about 102 K/s) applied to the water-cooled specimens prompted the formation of β-Sn dendrites and inhibited the formation of the AgZn
phase. After annealing for 20 h and 50 h, the corresponding microstructure changed significantly, especially the morphology
of the intermetallic compounds (IMCs) in the slowly cooled solder. IMC particles grew in order to minimize the system energy.
In addition, β-Sn dendrites grew coarser as the IMCs segregated along their grain boundaries in the water-cooled solder. Furthermore,
the Ag-Zn IMCs were suppressed in the water-cooled Sn-Ag-Zn-In solder. It is suggested that coarsening of the microstructure
led to significant softening during annealing of the investigated Sn-Ag-Zn-In alloys. 相似文献
8.
射频功率对a-C:F薄膜沉积速率和结构的影响 总被引:1,自引:1,他引:0
用射频等离子体增强型化学气相沉积法制备了a-C:F薄膜,并研究了射频功率对a-C:F薄膜沉积速率和结构的影响。用椭偏仪测量了薄膜的厚度,并用红外谱(FITR)结合Raman谱研究了其结构的变化。结果表明:薄膜沉积速率在10~14 nm/min之间,主要含有CFx和C=C键。随射频功率的升高,沉积速率先增大后减小,CF3的含量迅速减小,CF和CF2的含量略有增加,薄膜中r(F/C)呈下降的趋势。在较高功率下沉积的薄膜中出现了由sp2和sp3混合微晶结构。 相似文献
9.
Paul Lauro Sung K. Kang Won Kyoung Choi Da-Yuan Shih 《Journal of Electronic Materials》2003,32(12):1432-1440
The microstructure property relations of several Pb-free solders are investigated to understand the microstructural changes
during thermal and mechanical processes of Pb-free solders. The Pb-free solder alloys investigated include pure Sn, Sn-0.7%
Cu, Sn-3.5% Ag, and Sn-3.8% Ag-0.7% Cu (in weight percent). To reproduce a typical microstructure observed in solder joints,
the cooling rate, ingot size, and reflow conditions of cast alloys were carefully controlled. The cast-alloy pellets are subjected
to compressive deformation up to 50% and annealing at 150°C for 48 h. The microstructure of Pb-free solders is evaluated as
a function of alloy composition, plastic deformation, and annealing. The changes in mechanical property are measured by a
microhardness test. The work hardening in Sn-based alloys is found to increase as the amount of alloying elements and/or deformation
increases. The changes in microhardness upon deformation and annealing are correlated with the microstructural changes, such
as recrystallization or grain growth, in Pb-free solder alloys. 相似文献