The early stage dissolution of Ni and the nucleation of Ni–Sn intermetallic compound at the interface during the soldering of Sn–3.5Ag on a Ni substrate

2010 ◽  
Vol 108 (6) ◽  
pp. 063536 ◽  
Author(s):  
Yu-Wei Lin ◽  
Kwang-Lung Lin
Keyword(s):  
Intermetallic Compound ◽  
Early Stage ◽  
Ni Substrate

Direct observation of Fe-Al-Zn ternary intermetallic compound and its transformation during the early stage of hot-dip galvanizing

1993 ◽  
Vol 51 ◽  
pp. 1116-1117
Author(s):  
C. S. Lin ◽  
W. A. Chiou ◽  
M. Meshii
Keyword(s):  
Intermetallic Compound ◽  
Reaction Rate ◽  
Diffusion Rate ◽  
Early Stage ◽  
Zinc Bath ◽  
Steel Sheets ◽  
Direct Observations ◽  
Solid Iron ◽  
Iron And Zinc ◽  
Ternary Intermetallic Compound

The galvannealed steel sheets have received ever increased attention because of their excellent post-painting corrosion resistance and good weldability. However, its powdering and flaking tendency during press forming processes strongly impairs its performance. In order to optimize the properties of galvanneal coatings, it is critical to control the reaction rate between solid iron and molten zinc.In commercial galvannealing line, aluminum is added to zinc bath to retard the diffusion rate between iron and zinc by the formation of a thin layer of Al intermetallic compound on the surface of steel at initial hot-dip galvanizing. However, the form of this compound and its transformation are still speculated. In this paper, we report the direct observations of this compound and its transformation.The specimens were prepared in a hot-dip simulator in which the steel was galvanized in the zinc bath containing 0.14 wt% of Al at a temperature of 480 °C for 5 seconds and was quenched by liquid nitrogen.

Fabrication of Ni Sulfides by Thermal Sulfidation

2006 ◽  
Vol 510-511 ◽  
pp. 318-321
Author(s):  
Tae Hyun Nam ◽  
Cheol Am Yu ◽  
Dae Won Jung ◽  
Kwon Koo Cho
Keyword(s):  
Annealing Time ◽  
Annealing Temperature ◽  
Early Stage ◽  
Spherical Particles ◽  
Sulfur Pressure ◽  
X Ray ◽  
Ni Substrate ◽  
Initial Stage ◽  
Fabrication Parameters ◽  
Scanning Electron

The microstructure of Ni sulfides prepared by thermal sulfidation of pure Ni and their dependence of fabrication parameters were investigated by means of scanning electron microscopy and X-ray diffractions. Sulfidation was made by isothermally annealing Ni with the sulfur in vacuum sealed glass ampoules at 673 K for 120 – 600s under the sulfur pressure of 100 and 220 kPa. The sulfide layers formed in the early stage were found to consist of spherical particles smaller than 0.5um, which were grown and agglomerated with increasing annealing temperature. Thickness of sulfides developed on Ni substrate was found to increase with increasing annealing time and sulfur pressure. It was also found that compositions of dominant Ni sulfides changed with varying annealing time. At the initial stage, only Ni3S2 sulfide was formed on pure Ni, which was tightly bonded to Ni substrate. On increasing annealing time, NiS sulfide was formed. On further increasing annealing time, NiS1.97 sulfide was formed, which always coexisted with NiS sulfide. A mechanism for sulfidation of Ni is proposed as follows: 3Ni + 2S Ni3S2, Ni3S2 +S NiS, NiS + S NiS1.97

Interfacial Reaction and Shear Strength of Pb-Free Sn-3.5Ag/Ni BGA Solder Joints during Reflow

2005 ◽  
Vol 486-487 ◽  
pp. 289-292 ◽  
Author(s):  
Jeong Won Yoon ◽  
Sang Won Kim ◽  
Seung Boo Jung
Keyword(s):  
Shear Strength ◽  
Intermetallic Compound ◽  
Interfacial Reaction ◽  
Solder Joints ◽  
The Other ◽  
Reflow Time ◽  
Ni Substrate ◽  
Other Hand

The interfacial reaction between eutectic Sn-3.5wt.%Ag solder and Ni substrate resulted in the formation of Ni3Sn4 intermetallic compound (IMC) layer. After formation of the Ni3Sn4 IMC, its grain coarsened and faceted continuously in a prolonged reflow reaction. The thickness of the IMC layer increased with reflow time. On the other hand, the brittleness of the joints increased with increasing reflow time, and the fracture occurred at the interface. The deterioration of the shear strength was found to be predominantly caused by the formation of the thick Ni3Sn4 IMC layer.

The Influence of Cerium Ion Implantation on Early-Stage Oxidation Kinetics of Nickel

1996 ◽  
Vol 438 ◽  
Author(s):  
F. Czerwinski ◽  
J. A. Szpunar
Keyword(s):  
Oxidation Rate ◽  
Early Stage ◽  
Sol Gel ◽  
High Vacuum ◽  
Ultra High Vacuum ◽  
Physical Damage ◽  
Ni Substrate ◽  
Cerium Ion ◽  
Ni Oxidation ◽  
Order Of Magnitude

AbstractThe effect of implantation with 2×1016 ions/cm2 at 150 keV Ce+on the oxidation of polycrystalline high purity Ni was examined. The radiation damage and distribution of Ce implants in Ni substrate were additionally modified by post-implantation ultra-high vacuum annealing at 1073 K. Ce implants decreased the Ni oxidation rate at 973 K by approximately one order of magnitude, and this reduction was similar to that achieved by 14 nm thick CeO2 sol-gel coatings and by 4 nm thick coatings of CeO2 deposited on the same substrate by reactive sputtering. Physical damage introduced by radiation caused a slight increase in oxidation rate during the very initial stages. However, the essential improvement in the oxidation resistance was derived entirely from the chemical role of the implants. The beneficial effect of Ce was reduced when the implanted Ni substrate was vacuum-annealed prior to the oxidation.

Interfacial reactions and shear strength on Cu and electrolytic Au/Ni metallization with Sn-Zn solder

2006 ◽  
Vol 21 (6) ◽  
pp. 1590-1599 ◽  
Author(s):  
Jeong-Won Yoon ◽  
Seung-Boo Jung
Keyword(s):  
Thermal Expansion ◽  
Shear Strength ◽  
Intermetallic Compound ◽  
Aging Time ◽  
Interfacial Reaction ◽  
Joint Strength ◽  
Ball Grid Array ◽  
Fast Reaction ◽  
Cu Substrate ◽  
Ni Substrate

The interfacial reaction between eutectic Sn-9 wt% Zn solder and two different kinds of ball-grid-array substrates (Cu and Au/Ni electroplated Cu) during aging at 150 °C and the shear strength of the resulting joints were investigated. In the Sn-9Zn/Cu joints, only Cu5Zn8 intermetallic compound (IMC) was observed between the solder and Cu layer during the first 100 h of aging. After aging for 1000 h, the layer-type Cu5Zn8 IMC layer was disrupted at the interface, causing it to act as a channel for the diffusion of Sn. As a result, Cu6Sn5 and Cu3Sn IMCs were formed underneath the Cu5Zn8 IMC layer. This interfacial reaction significantly degraded the joint strength. In the case of the Au/Ni/Cu substrate, an AuZn3 IMC layer formed at the interface because of the fast reaction between Au and Zn. In addition, the AuZn3 IMC layer became detached from the interface during reflow. The detachment of the AuZn3 IMC layer is presumably from the mismatch in the coefficients of thermal expansion and weak adhesion between the AuZn3 IMC layer and Ni layer caused by the depletion of the Au layer. When the aging time was extended to 100 h, Ni5Zn21 IMC was observed on the Ni substrate. The shear strength of the aged Sn-9Zn/Au/Ni/Cu joint was significantly related to the detachment of the AuZn3 IMC layer. After aging at 150 °C, fracturing occurred on the detached AuZn3 IMC layer. To ensure the reliability of the Sn-Zn/Au/Ni/Cu joint, the detachment of the AuZn3 IMC needs to be prevented.

Dislocation Substructures Produced During Tensile, Creep, and Fatigue Deformation of Ti3Al at 700°C

1977 ◽  
Vol 35 ◽  
pp. 272-273
Author(s):  
S. M. L. Sastry
Keyword(s):  
Intermetallic Compound ◽  
Strain Rate ◽  
Tensile Creep ◽  
Slip Systems ◽  
Slip Vector ◽  
Superlattice Structure ◽  
Slip Activity ◽  
Dislocation Arrangement ◽  
Ordered Intermetallic ◽  
Tangled Dislocation

Ti3Al is an ordered intermetallic compound having the DO19-type superlattice structure. The compound exhibits very limited ductility in tension below 700°C because of a pronounced planarity of slip and the absence of a sufficient number of independent slip systems. Significant differences in slip behavior in the compound as a result of differences in strain rate and mode of deformation are reported here.Figure 1 is a comparison of dislocation substructures in polycrystalline Ti3Al specimens deformed in tension, creep, and fatigue. Slip activity on both the basal and prism planes is observed for each mode of deformation. The dominant slip vector in unidirectional deformation is the a-type (b) = <1120>) (Fig. la). The dislocations are straight, occur for the most part in a screw orientation, and are arranged in planar bands. In contrast, the dislocation distribution in specimens crept at 700°C (Fig. lb) is characterized by a much reduced planarity of slip, a tangled dislocation arrangement instead of planar bands, and an increased incidence of nonbasal slip vectors.

Atomic structure of interface of intermetallic compound TiAl and nitride Ti2AIN using HREM and image processing

1991 ◽  
Vol 49 ◽  
pp. 570-571
Author(s):  
E. Sukedai ◽  
H. Mabuchi ◽  
H. Hashimoto ◽  
Y. Nakayama
Keyword(s):  
Mechanical Properties ◽  
Image Processing ◽  
Composite Material ◽  
Intermetallic Compound ◽  
Side Surface ◽  
High Resolution Electron Microscopy ◽  
Hexagonal Structure ◽  
Second Phase ◽  
Resolution Electron ◽  
Compound Tial

In order to improve the mechanical properties of an intermetal1ic compound TiAl, a composite material of TiAl involving a second phase Ti2AIN was prepared by a new combustion reaction method. It is found that Ti2AIN (hexagonal structure) is a rod shape as shown in Fig.1 and its side surface is almost parallel to the basal plane, and this composite material has distinguished strength at elevated temperature and considerable toughness at room temperature comparing with TiAl single phase material. Since the property of the interface of composite materials has strong influences to their mechanical properties, the structure of the interface of intermetallic compound and nitride on the areas corresponding to 2, 3 and 4 as shown in Fig.1 was investigated using high resolution electron microscopy and image processing.

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