Technology for obtaining of Niobium and Tantalum coatings on the copper Substrate

This paper elucidates the effect of isothermal ageing at temperature of 85 °C, 125 °C and 150 °C for 100, 500 and 1000 h on Sn-3.0Ag-0.5Cu (SAC305) lead-free solder with the addition of 1 wt% kaolin geopolymer ceramic (KGC) reinforcement particles. SAC305-KGC composite solders were fabricated through powder metallurgy using a hybrid microwave sintering method and reflowed on copper substrate printed circuit board with an organic solderability preservative surface finish. The results revealed that, the addition of KGC was beneficial in improving the total thickness of interfacial intermetallic compound (IMC) layer. At higher isothermal ageing of 150 °C and 1000 h, the IMC layer in SAC305-KGC composite solder was towards a planar-type morphology. Moreover, the growth of total interfacial IMC layer and Cu3Sn layer during isothermal ageing was found to be controlled by bulk diffusion and grain-boundary process, respectively. The activation energy possessed by SAC305-KGC composite solder for total interfacial IMC layer and Cu3Sn IMC was 74 kJ/mol and 104 kJ/mol, respectively. Based on a lap shear test, the shear strength of SAC305-KGC composite solder exhibited higher shear strength than non-reinforced SAC305 solder. Meanwhile, the solder joints failure mode after shear testing was a combination of brittle and ductile modes at higher ageing temperature and time for SAC305-KGC composite solder.

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Characterization of Soldering Alloy Type Bi-Ag-Ti and the Study of Ultrasonic Soldering of Silicon and Copper

Metals ◽

10.3390/met11040624 ◽

2021 ◽

Vol 11 (4) ◽

pp. 624

Author(s):

Roman Kolenak ◽

Igor Kostolny ◽

Jaromir Drapala ◽

Paulina Babincova ◽

Peter Gogola

Keyword(s):

Eutectic Reaction ◽

Research Work ◽

Copper Substrate ◽

Liquid Bismuth ◽

Alloy Type ◽

Average Shear Strength ◽

Average Shear ◽

The Matrix ◽

Solder Microstructure ◽

Ultrasonic Soldering

The aim of the research work was to characterize the soldering alloy type Bi-Ag-Ti and to study the direct soldering of silicon and copper. Bi11Ag1.5Ti solder has a broad melting interval. Its scope depends mainly on the content of silver and titanium. The solder begins to melt at the temperature of 262.5 ∘C and full melting is completed at 405 ∘C. The solder microstructure consists of a bismuth matrix with local eutectics. The silver crystals and titanium phases as BiTi2 and Bi9Ti8 are segregated in the matrix. The average tensile strength of the solder varies around 42 MPa. The bond with silicon is formed due to interaction of active titanium with the silicon surface at the formation of a reaction layer, composed of a new product, TiSi2. In the boundary of the Cu/solder an interaction between the liquid bismuth solder and the copper substrate occurs, supported by the eutectic reaction. The mutual solubility between the liquid bismuth solder is very limited, on both the Bi and the Cu side. The average shear strength in the case of a combined joint of Si/Cu fabricated with Bi11Ag1.5Ti solder is 43 MPa.

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Electrodeposition of silicon nanospheres on rGO coated copper substrate for lithium-ion batteries

Materials Today Proceedings ◽

10.1016/j.matpr.2020.12.515 ◽

2021 ◽

Author(s):

Anjali Vanpariya ◽

Sakshum Khanna ◽

Priyanka Marathey ◽

Sagar Paneliya ◽

Indrajit Mukhopadhyay

Keyword(s):

Lithium Ion Batteries ◽

Copper Substrate ◽

Lithium Ion

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Effect of ultrasonic vibration on the wetting behavior of molten tin on copper substrate

Journal of Materials Science Materials in Electronics ◽

10.1007/s10854-020-04882-7 ◽

2021 ◽

Author(s):

Xuemin Sun ◽

Weiyuan Yu ◽

Fengfeng Wang ◽

Yanhong Wang

Keyword(s):

Ultrasonic Vibration ◽

Copper Substrate ◽

Wetting Behavior

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Influence of Nanoscale Textured Surfaces and Subsurface Defects on Friction Behaviors by Molecular Dynamics Simulation

Nanomaterials ◽

10.3390/nano9111617 ◽

2019 ◽

Vol 9 (11) ◽

pp. 1617 ◽

Cited By ~ 1

Author(s):

Ruiting Tong ◽

Zefen Quan ◽

Yangdong Zhao ◽

Bin Han ◽

Geng Liu

Keyword(s):

Molecular Dynamics ◽

Molecular Dynamics Simulation ◽

Friction Force ◽

Copper Substrate ◽

Dynamics Simulation ◽

Textured Surfaces ◽

Friction Forces ◽

Subsurface Structures ◽

Texture Orientation ◽

Subsurface Defects

In nanomaterials, the surface or the subsurface structures influence the friction behaviors greatly. In this work, nanoscale friction behaviors between a rigid cylinder tip and a single crystal copper substrate are studied by molecular dynamics simulation. Nanoscale textured surfaces are modeled on the surface of the substrate to represent the surface structures, and the spacings between textures are seen as defects on the surface. Nano-defects are prepared at the subsurface of the substrate. The effects of depth, orientation, width and shape of textured surfaces on the average friction forces are investigated, and the influence of subsurface defects in the substrate is also studied. Compared with the smooth surface, textured surfaces can improve friction behaviors effectively. The textured surfaces with a greater depth or smaller width lead to lower friction forces. The surface with 45° texture orientation produces the lowest average friction force among all the orientations. The influence of the shape is slight, and the v-shape shows a lower average friction force. Besides, the subsurface defects in the substrate make the sliding process unstable and the influence of subsurface defects on friction forces is sensitive to their positions.

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