Discontinuous coarsening behavior of Ni2MnAl intermetallic compound during isothermal aging treatment of Fe-Mn-Ni-Al alloys

2010 ◽  
Vol 59 (S1) ◽  
pp. S135-S140 ◽  
Author(s):  
Y.-U. Heo ◽  
M. Takeguchi ◽  
K. Furuya ◽  
H.-C. Lee
2006 ◽  
Vol 15-17 ◽  
pp. 1001-1007 ◽  
Author(s):  
Jeong Won Yoon ◽  
Seung Boo Jung

The interaction between Cu/Sn-Ag and Sn-Ag/Ni interfacial reactions has been studied during isothermal aging at 150°C for up to 1000h using a Cu/Sn-3.5Ag/ENIG sandwich solder joint. A typical scallop-type Cu-Sn intermetallic compound (IMC) layer formed at the upper Sn-Ag/Cu interface after reflowing. On the other hand, a (Cu,Ni)6Sn5 IMC layer was observed at the Sn-Ag/ENIG interface. The Cu in the (Cu,Ni)6Sn5 IMC layer formed on the Ni side has to be contributed from the dissolution of the opposite Cu metal pad or Cu-Sn IMC layer. When the dissolved Cu arrived at the interface of the Ni pad, the (Cu,Ni)6Sn5 IMC layer formed on the Ni interface, preventing the Ni pad from reacting with the solder. Although a long isothermal aging treatment at 150°C was performed, any Ni was not detected in the Cu-Sn IMC layer formed on the Cu side. Compared to the single Sn-Ag/ENIG solder joint, the formation of the (Cu,Ni)6Sn5 IMC layer of the Cu/Sn-Ag/ENIG sandwich joint retarded effectively the consumption of the Ni from the electroless Ni-P layer.


JOM ◽  
2019 ◽  
Vol 72 (4) ◽  
pp. 1540-1551 ◽  
Author(s):  
X. Y. Liu ◽  
C. C. Wang ◽  
X. Wang ◽  
Z. J. Zhao ◽  
M. Wu ◽  
...  

Metals ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 819
Author(s):  
Changsheng Li ◽  
Kun Li ◽  
Jingbo Dong ◽  
Jinyi Ren ◽  
Yanlei Song

The effect of aging on the precipitates, mechanical and magnetic properties of Fe-21Cr-15Ni-6Mn-Nb low magnetic stainless steel were investigated. The steel was aged at 550–750 °C for 2 h after solution heat treatment at 1100 °C for 1 h. During the aging treatment, the (Nb, V)(C, N) particles gradually precipitated in the grain, which were coherent or semi-coherent with the matrix. When the aging temperature was beyond 650 °C, the coarsening rate of (Nb, V)(C, N) particles increase rapidly and the coherent orientation between (Nb, V)(C, N) particles and the matrix was lost gradually. Meanwhile, coarse M23C6 was distributed at the grain boundary with chain shape, which was non-coherent with the matrix. The coarsening behavior of (Nb, V)(C, N) precipitates in the grain was analyzed, and the size of the particles precipitated after aging treatment at 650°C for different time was calculated and studied. After aging treatment at 650 °C for 2 h, the yield strength and tensile strength of the stainless steel was 705.6 MPa and 1002.3 MPa, the elongation and the relative magnetic permeability was 37.8% and 1.0035, respectively.


Materials ◽  
2019 ◽  
Vol 12 (6) ◽  
pp. 936 ◽  
Author(s):  
Min-Soo Kang ◽  
Do-Seok Kim ◽  
Young-Eui Shin

This study investigated the suppression of the growth of the intermetallic compound (IMC) layer that forms between epoxy solder joints and the substrate in electronic packaging by adding graphene nano-sheets (GNSs) to 96.5Sn–3.0Ag–0.5Cu (wt %, SAC305) solder whose bonding characteristics had been strengthened with a polymer. IMC growth was induced in isothermal aging tests at 150 °C, 125 °C and 85 °C for 504 h (21 days). Activation energies were calculated based on the IMC layer thickness, temperature, and time. The activation energy required for the formation of IMCs was 45.5 KJ/mol for the plain epoxy solder, 52.8 KJ/mol for the 0.01%-GNS solder, 62.5 KJ/mol for the 0.05%-GNS solder, and 68.7 KJ/mol for the 0.1%-GNS solder. Thus, the preventive effects were higher for increasing concentrations of GNS in the epoxy solder. In addition, shear tests were employed on the solder joints to analyze the relationship between the addition of GNSs and the bonding characteristics of the solder joints. It was found that the addition of GNSs to epoxy solder weakened the bonding characteristics of the solder, but not critically so because the shear force was higher than for normal solder (i.e., without the addition of epoxy). Thus, the addition of a small amount of GNSs to epoxy solder can suppress the formation of an IMC layer during isothermal aging without significantly weakening the bonding characteristics of the epoxy solder paste.


1999 ◽  
Vol 14 (5) ◽  
pp. 1760-1770 ◽  
Author(s):  
H. G. Jiang ◽  
H. M. Hu ◽  
E. J. Lavernia

The synthesis of nanocrystalline Fe, Fe–4 wt% Al, and Fe–10 wt% Al solid solutions by SPEX ball milling has been studied. The microstructural evolution during ball milling, as well as subsequent heat treatment, has been characterized. The results demonstrate that ball milling promotes the formation of αFe–4 wt% Al and αFe–10 wt% Al solid solutions by reducing the activation energy of these alloys and generating thermal energy during this process. For Fe–10 wt% Al powders milled for various time intervals up to approximately 20 min, the FeAl intermetallic compound is formed. For alloys annealed at temperatures ranging from 600 to 1000 °C, the addition of 10 wt% Al to Fe significantly enhances the thermal stability of the nanocrystalline Fe–Al alloys. Interestingly, the addition of Al within the range of 4–10 wt% seems to have little effect on the thermal stability of these alloys annealed under the same conditions. Also, the thermal stability improves for alloys milled in air as opposed to those processed using Ar.


2016 ◽  
Vol 700 ◽  
pp. 123-131 ◽  
Author(s):  
Rita Mohd Said ◽  
Mohd Arif Anuar Mohd Salleh ◽  
Mohd Nazree Derman ◽  
Mohd Izrul Izwan Ramli ◽  
Norhayanti Mohd Nasir ◽  
...  

This work investigated the effects of 1.0 wt. % TiO2 particles addition into Sn-Cu-Ni solder paste to the growth of the interfacial intermetallic compound (IMC) on Cu substrate after isothermal aging. Sn-Cu-Ni solder paste with TiO2 particles were mechanically mixed to fabricate the composite solder paste. The composite solder paste then reflowed in the reflow oven to form solder joint. The reflowed samples were then isothermally aged 75, 125 and 150 ° C for 24 and 240 h. It was found that the morphology of IMCs changed from scallop-shape to a more uniform planar shape in both Sn-Cu-Ni/Cu joints and Sn-Cu-Ni-TiO2 /Cu joint. Cu6Sn5 and Cu3Sn IMC were identified and grew after prolong aging time and temperature. The IMCs thickness and scallop diameter of composite solder paste were reduced and the growth of IMCs thickness after isothermal aging become slower as compared to unreinforced Sn-Cu-Ni solder paste. It is suggested that TiO2 particles have influenced the evolution and retarded the growth of interfacial IMCs.


2016 ◽  
Vol 45 (12) ◽  
pp. 6067-6078 ◽  
Author(s):  
Tomasz Gancarz ◽  
Janusz Pstrus ◽  
Grzegorz Cempura ◽  
Katarzyna Berent

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