scholarly journals Infrared Brazing of CoCrFeMnNi Equiatomic High Entropy Alloy Using Nickel-Based Braze Alloys

Entropy ◽  
2019 ◽  
Vol 21 (3) ◽  
pp. 283 ◽  
Author(s):  
Chieh Lin ◽  
Ren-Kae Shiue ◽  
Shyi-Kaan Wu ◽  
Huai-Li Huang
Keyword(s):  
Shear Strength ◽  
Grain Boundary ◽  
High Entropy Alloy ◽  
Solidification Shrinkage ◽  
Vacuum Brazing ◽  
High Entropy ◽  
Average Shear Strength ◽  
Average Shear ◽  
Brazed Joints ◽  
Liquidus Temperatures

Infrared vacuum brazing of CoCrFeMnNi high entropy alloy (HEA) using BNi-2 and MBF601 fillers has been investigated. Both brazes show poor wettability at temperatures only 20 °C above their liquidus temperatures. However, the wettability of BNi-2 and MBF601 fillers on CoCrFeMnNi HEA is greatly improved with increasing the test temperatures, 50 °C above their liquidus temperatures. The BNi-2 brazed joints are dominated by Ni-rich matrix with huge CrB and a few tiny boride precipitates. Average shear strengths of joints increase with increasing brazing temperature and/or time, and fracture location changes from blocky CrB in the brazed zone to grain boundary boride in the substrate. The MBF601 brazed joints are composed of CoCrFeMnNi-based matrix, particles of B/Co/Cr/Fe/Mn/Ni/P compounds, and some phosphides form along the grain boundaries of the substrate. The specimen brazed with MBF601 filler foil at 1050 °C for 600 s has the highest average shear strength of 321 MPa, while that brazed at 1080 °C for 600 s has a lower average shear strength of 271 MPa due to the presence of solidification shrinkage voids.

Vacuum Brazing Incoloy 800 Using the Copper Foil

2015 ◽  
Vol 1101 ◽  
pp. 99-103
Author(s):  
Cheng Yen Wang ◽  
Ren Kae Shiue
Keyword(s):  
Shear Strength ◽  
Copper Foil ◽  
Vacuum Furnace ◽  
Vacuum Brazing ◽  
Average Shear Strength ◽  
Average Shear ◽  
Incoloy 800 ◽  
Brazed Joints ◽  
Brazed Joint ◽  
Time Average

The purpose of this research is focused on vacuum furnace brazing Incoloy 800 (IN-800) using the copper filler foil. Microstructural evolution and shear strength of brazed joints for various brazing conditions has been evaluated in the experiment. The Cu-rich matrix dominates entire brazed joint. The width of Cu-rich matrix is decreased with increasing the brazing temperature and/or time. Average shear strength of the joint is approximately 215 MPa. Dimple dominated fracture is widely observed for the specimen brazed below 1160oC. However, cleavage dominated fracture is found for the specimen brazed at 1200oC. It is advised that copper brazing IN-800 alloy should be confined below 1160oC.

scholarly journals Microstructure and Shear Strength of Brazing High Entropy TiZrHfNbMo Alloy and Si3N4 Ceramics Joints

Crystals ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 472
Author(s):  
Xiaohong Wang ◽  
Duo Dong ◽  
Xiaohong Yang ◽  
Peng Huang ◽  
Kangqiao Shi ◽  
...  
Keyword(s):  
Solid Solution ◽  
Shear Strength ◽  
Intermetallic Compounds ◽  
Reaction Layer ◽  
Interfacial Microstructure ◽  
High Entropy Alloy ◽  
Si3n4 Ceramic ◽  
High Entropy ◽  
Brazed Joints ◽  
Brazed Joint

The effects of different brazing processes on the interfacial microstructure and shear strength of TiZrHfNbMo high-entropy alloy (HEAS) and Si3N4 ceramic brazed joints were studied. There is no obvious defect in a brazed TiZrHfNbMo HEAS/AgCuTi/Si3N4 ceramic joint, and the two materials have good metallurgical bonding. The typical interface microstructure is Si3N4/Ti5Si3/Ag solid solution +Cu (s,s)+ CuTi/Cu2Ti/Cu4Ti + TiCu(Hf,Zr)NbMo/TiZrHfNbMo HEAs. With the increase of brazing temperature, the dispersed CuTi phase agglomerates in the brazed joint, and acts as the nucleate of the Cu-based solid solution. The thickness of the reaction layer increases with the increase of phases in the reaction layer on both sides of the joint. When the brazing temperature is 800 °C, 820 °C, 840 °C and 860 °C, the shear strength of the brazed joint is 30 MPa, 72 MPa, 86 MPa and 21 MPa, respectively. The formation of CuTi and Ti5Si3 intermetallic compounds increases the thickness of the reaction layer, and improves the strength of the joint. However, excessive CuTi and Ti5Si3 intermetallic compounds lead to a significant decrease in joint strength. The grain coarsening of the joint can also affect the strength of the joint.

scholarly journals Microstructure and Physical Properties of Alloy Brazed with Filler by Mapping Scanning Analysis and Wettability Test

2021 ◽  
Vol 2083 (2) ◽  
pp. 022086
Author(s):  
Xiupeng Li ◽  
Yunyue Li ◽  
Sujuan Zhong ◽  
Yuanxun Shen ◽  
Weimin Long ◽  
...  
Keyword(s):  
Heat Treatment ◽  
Shear Strength ◽  
Filler Metal ◽  
Solidus Temperature ◽  
Spreading Effect ◽  
Average Shear Strength ◽  
Average Shear ◽  
Brazed Joints ◽  
Brazed Joint ◽  
New Type

Abstract In this paper, a new type of AlSiMgCuNiAg filler metal was developed. The solidus temperature of the filler metal is 509.1°C and the liquidus temperature is 531.3°C. The filler metal has a good wetting and spreading effect on the surface of 6061 aluminum alloy. The CuAl2 phase in the brazing seam was greatly aggregated after brazed, while the CuAl2 phase was reduced and Mg2Si strengthening phase was formed when the brazed joints with heat treatment. The average shear strength of the brazed joint without heat treatment was 47.1MPa, and the average shear strength of the brazed joint with heat treatment reached to 108.7Mpa. The strength of the brazed joint with heat treatment was increased by about 131% relative to the strength of the brazed joint without heat treatment.

scholarly journals Micro-Brazing of Stainless Steel Using Ni-P Alloy Plating

2019 ◽  
Vol 9 (6) ◽  
pp. 1094
Author(s):  
Shubin Liu ◽  
Ikuo Shohji ◽  
Makoto Iioka ◽  
Anna Hashimoto ◽  
Junichiro Hirohashi ◽  
...  
Keyword(s):  
Stainless Steel ◽  
Shear Strength ◽  
Solid Solutions ◽  
Joint Strength ◽  
Filler Metal ◽  
Average Shear Strength ◽  
Average Shear ◽  
Brazed Joints ◽  
Brazed Joint ◽  
Alloy Plating

A Ni-P plated layer of 20 μm thickness containing 11 wt.% P was formed on the surface of a stainless steel (SUS304) plate by electroplating. The microstructure and joint strength of the brazed joint with the electroplated Ni-11P layer were investigated. The results indicated that the filler metal was homogeneously distributed between the SUS304 plates and no voids or flaws formed in the brazed filler zone. Fe-Ni-Cr solid solutions were formed at the brazed interface. Moreover, P was mainly concentrated in such brazed filler zone to form P-containing phases. The average shear strength of the brazed joints was determined to be 47.3 MPa. The results demonstrated that the brazing of SUS304 plates using the electroplated Ni-11P layer as the filler metal was successfully realized.

Thermal stability and grain boundary strengthening in ultrafine-grained CoCrFeNi high entropy alloy composite

2017 ◽  
Vol 134 ◽  
pp. 426-433 ◽  
Author(s):  
Praveen Sathiyamoorthi ◽  
Joysurya Basu ◽  
Sanjay Kashyap ◽  
K.G. Pradeep ◽  
Ravi Sankar Kottada
Keyword(s):  
Thermal Stability ◽  
Grain Boundary ◽  
High Entropy Alloy ◽  
Alloy Composite ◽  
High Entropy ◽  
Ultrafine Grained ◽  
Grain Boundary Strengthening

scholarly journals Synthesis of high-entropy alloy thin films via grain boundary diffusion–assisted solid-state alloying

2022 ◽  
Vol 207 ◽  
pp. 114302
Author(s):  
Seungjin Nam ◽  
Sang Jun Kim ◽  
Moon J. Kim ◽  
Manuel Quevedo-Lopez ◽  
Jun Yeon Hwang ◽  
...  
Keyword(s):  
Thin Films ◽  
Solid State ◽  
Grain Boundary ◽  
Boundary Diffusion ◽  
Grain Boundary Diffusion ◽  
High Entropy Alloy ◽  
High Entropy

Shear strength and cracking behavior of Cr coatings on zirconium alloy fuel claddings at different strain rates

2021 ◽  
pp. 2150194
Author(s):  
Xiulin Yan ◽  
Ruiqian Zhang ◽  
Yan Liu ◽  
Yunhua Zhang ◽  
Hui Chen
Keyword(s):  
Shear Strength ◽  
Interfacial Shear Strength ◽  
Strain Rates ◽  
Cracking Behavior ◽  
Shear Lag Model ◽  
Loading Direction ◽  
Average Shear Strength ◽  
Average Shear ◽  
Lag Model ◽  
Cr Coating

Cr coating on Zr-based fuel tubes is a potential approach for the development of accident tolerant fuels (ATF). To settle the cracking behavior and quantitative evaluation of shear strength of Cr coating under different loading conditions, the average shear strength between Cr coating and zircaloy substrate has been estimated using a modified shear-lag model in this paper. Its key parameters are determined experimentally, and the tensile method has been used to research the cracking behavior of Cr coating under different strain rates. The results show that with the increase of strain rate, the interfacial shear strength increases because of the decrease of cracking spacing, while the shear strength changes erratically with the coating thickness increases. Furthermore, abundant two unequal-crack-spacings and few two equal-crack-spacings are observed which are perpendicular to the loading direction.

Diffusion Barrier Effect of Carbide Layer on Bonding Characteristics of Ti/Steel Clad

1996 ◽  
Vol 458 ◽  
Author(s):  
Y. Morizono ◽  
M. Nishida ◽  
A. Chiba
Keyword(s):  
Stainless Steel ◽  
Shear Strength ◽  
Reaction Layer ◽  
Holding Time ◽  
Barrier Effect ◽  
Parent Materials ◽  
Prolonged Annealing ◽  
Average Shear Strength ◽  
Average Shear ◽  
Bonding Characteristics

ABSTRACTBonding characteristics and interfacial microstructures in explosively welded Ti/stainless steel clad of the as-welded and annealed states were investigated. In case of Ti/SUS430 ferritic stainless steel combination, the average shear strength of an as-welded clad was 555 MPa, and metastable phases such as amorphous and fine crystalline phases were observed at the interface. These were considered to be the trace of melting and subsequently rapid solidification at the contact surface of both the parent materials. By annealing below 1173 K, the strength gradually decreased with increasing holding time. The average shear strength of the clad annealed at 1073 K for 360 ks was 242 MPa, while that of the clad annealed at 1273 K abruptly decreased down to 107 MPa with increasing holding time up to 360 ks. The reaction layer formed at the interface consisted only of TiC in the former. On the other hand, the coexistence of TiC, TiFe, TiFe2 and χ was observed at the interface in the latter. The TiC in the former was considered to serve as a barrier for diffusion of Ti, Fe and Cr across the interface and to suppress the formation of intermetallic compounds. As a result, the growth of reaction layer was inhibited and high bonding strength was preserved even after prolonged annealing. The results of the Combination of Ti and SUS304 austenitic stainless steel were also discussed.

scholarly journals Microstructure and Strength of γ-TiAl Alloy/Inconel 718 Brazed Joints

2012 ◽  
Vol 730-732 ◽  
pp. 835-840 ◽  
Author(s):  
Elsa W. Sequeiros ◽  
Anibal Guedes ◽  
Ana Maria Pires Pinto ◽  
Manuel F. Vieira ◽  
Filomena Viana
Keyword(s):  
Inconel 718 ◽  
Tial Alloy ◽  
Electron Backscatter Diffraction ◽  
Braze Alloy ◽  
Base Material ◽  
Industrial Applications ◽  
Processing Conditions ◽  
Average Shear Strength ◽  
Average Shear ◽  
Brazed Joints

Intermetallics and superalloys brazing development is a current topic owing the extending use of these alloys in industrial applications. In this work a γ-TiAl alloy was joined to Inconel 718 by active metal brazing, using Incusil-ABA as filler. Joining was performed at 730 °C, 830 °C and 930 °C, with a 10 min dwelling time. The interfaces were characterized by Scanning Electron Microscopy (SEM), Energy Dispersive X-ray Spectroscopy (EDS) and Electron Backscatter Diffraction (EBSD). For all processing conditions, the reaction between the base materials and the braze alloy produced multilayered interfaces. For all processing temperatures tested (Ag), (Cu), AlNi2Ti and AlCu2Ti were identified at the interface. Raising the brazing temperature increased the thickness of the interface and coarsened its microstructure. The increase of the extension of the interface was essentially due to the growth of the reaction layers formed near each base material, which were found to be mainly composed of intermetallic compounds. The mechanical behavior of the joints, at room temperature, was assessed by microhardness and shear tests. For all processing conditions the hardness decreases from periphery towards the Ag-rich centre of the joints. Brazing at 730 °C for 10 min produced the joints with the highest average shear strength (228±83 MPa). SEM and EDS analysis of the fracture surfaces revealed that fracture of joints always occurred across the interface, preferentially through the hard layer, essentially composed of AlNi2Ti, resulting from the reaction between Inconel 718 and the braze alloy.

Segregation-driven grain boundary spinodal decomposition as a pathway for phase nucleation in a high-entropy alloy

2019 ◽  
Vol 178 ◽  
pp. 1-9 ◽  
Author(s):  
Linlin Li ◽  
Zhiming Li ◽  
Alisson Kwiatkowski da Silva ◽  
Zirong Peng ◽  
Huan Zhao ◽  
...  
Keyword(s):  
Grain Boundary ◽  
Spinodal Decomposition ◽  
High Entropy Alloy ◽  
High Entropy ◽  
Phase Nucleation
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