1I1 Optimum Joint Clearance on Brazed Joint of Cemented Carbide/Silver Brazing Filler Metal

2013 ◽  
Vol 2013 (0) ◽  
pp. 269-270
Author(s):  
Kyogo WATABE ◽  
Kazuya MORI
Author(s):  
Meribe Richard Chukwuma ◽  
Kazuya MORI ◽  
Kento Takenouchi ◽  
Yuki Fijishita ◽  
Takeshi Eguchi ◽  
...  

2012 ◽  
Vol 445 ◽  
pp. 759-764 ◽  
Author(s):  
Seyed Ali Asghar Akbari Mousavi ◽  
P. Sherafati ◽  
M.M. Hoseinion

In this study the wettability, microstructure and mechanical properties of joining between cemented carbide and CK35 steel which brazed with two filler metals, L-Ag40Cd and L-Ag34Cd, were investigated. Wettability test shows that with increase of brazing time, the contact angle decreases and the best situation was resulted in the 20 minute brazing. Microscopic investigation of the brazed area with both filler metal shows that there is a copper enriched primary phase and eutectic microstructure in the silver enriched matrix which composed of copper enriched particles. The amount and the dispersion of precipitates are depended upon type of filler metal and brazing temperature. The results show that brazing with L-Ag34Cd filler metal at 800 °C exhibit superior shear strength in the level of 108 MPa.


2021 ◽  
Vol 1016 ◽  
pp. 997-1002
Author(s):  
Hikaru Nagata ◽  
Masa Ono ◽  
Yasuyuki Miyazawa ◽  
Yuji Hayashi ◽  
Yoshio Bizen

To clarify the effect of the acid solution type on corrosion resistance, the corrosion behavior of stainless steel brazed joints in HCl aqueous solution was evaluated through electrochemical measurements. Anodic polarization curves of a ferritic stainless-steel base metal, Ni-based brazing filler metals, and a brazed joint were recorded. In addition, in situ observations were conducted to observe the corrosion behavior of each structure of the brazed joint. Corrosion potentials of the brazing filler metal were lower than that of the base metal. In situ observations of the brazed joint revealed the order of corrosion in aqueous hydrochloric acid. According to the electrochemical measurements, under an actual corrosive environment, the brazing filler metal can function as an anode and selectively corrode. In addition, the anodic polarization curve of the brazed joint showed values between those of the polarization curves of the brazing filler metal and the base metal, indicating that the corrosion resistance could be electrochemically evaluated in HCl aqueous solution.


2018 ◽  
Vol 37 (9-10) ◽  
pp. 863-872 ◽  
Author(s):  
Yun Luo ◽  
Chuanlong Wang ◽  
Wenchun Jiang ◽  
Yu Wan ◽  
Weiya Zhang ◽  
...  

AbstractIn the brazing process, some brazing defects like semicircular or straight type are generated due to incomplete filling. In this paper, the creep damage and creep crack initiation (CCI) time of Hastelloy C276-BNi2 brazed joint with defects are investigated by a ductility exhaustion damage model. The effects of defect dimension and filler metal thickness are also discussed. The results show that the different defects have different creep damage distributions and CCI times. The maximum creep damage is located at the defect frontier due to the larger stress concentration. With the increase of semicircular defect radius and straight defect length, the CCI time decreases. The creep fracture is inclined to generate in semicircular defect for the smaller defect area ratio, while it is easy to generate in straight defect for the bigger defect area ratio. As the filler metal thickness increases, the CCI time increases. For the thicker filler metal, the creep crack is easy to initiate in semicircular defect.


Author(s):  
Xiao Huang ◽  
Scott Yandt ◽  
Doug Nagy ◽  
Matthew Yao

Modern gas and steam turbine components are subject to severe thermomechanical loads and extremely high temperature in order to provide increased performance and efficiency. Most high temperature turbine components are made of superalloys specifically developed for high temperature and high mechanical stress applications but at considerable cost. Defects may occur during manufacturing of superalloy castings as well as after service. Repair of these components, rather than replacement, helps to reduce the life cycle cost. Wide gap brazing is a cost effective and reliable means to repair gas turbine hot section components with defect sizes exceeding 0.3 mm. With proper control of the braze alloy and brazing cycle, the repaired region has been reported to posses mechanical properties approaching that of the parent materials. In order to further improve the mechanical properties of the repaired region and to explore the possibility of employing the wide gap brazing method to repair single crystal components in the future, three alloying additions, Ruthenium (Ru), Rhenium (Re) and yttria (Y2O3), were incorporated into the braze filler metal by mechanical alloying. The microstructures of the wide gap brazed joints with Ru, Re and yttria additions were studied and compared to a braze joint with standard wide gap braze alloys of IN738 and AWS BNi-9. It has been found that two types of borides formed in all braze alloys, namely eutectic γ-Ni-rich and boride phases and discrete boride containing primarily Cr and W (or Ru). The addition of Ru to the filler metal did not seem to modify the microstructural constituents after brazing. However, Ru partitioned strongly to the discrete borides. No isolated elemental Ru region was observed. On the other hand, Re addition was found to change the occurrence and distribution of both types of borides. The eutectic boride constituent was significantly reduced and finer discrete boride particles were observed. The addition of yttria did not change the boride formation but led to the generation of more voids in the brazed joint.


Metals ◽  
2019 ◽  
Vol 9 (2) ◽  
pp. 198 ◽  
Author(s):  
Peng Xue ◽  
Yang Zou ◽  
Peng He ◽  
Yinyin Pei ◽  
Huawei Sun ◽  
...  

The microstructure and properties of a Cu/304 stainless steel dissimilar metal joint brazed with a low silver Ag16.5CuZnSn-xGa-yCe braze filler after aging treatment were investigated. The results indicated that the addition of Ce could reduce the intergranular penetration depth of the filler metal into the stainless steel during the aging process. The minimum penetration depth in the Ag16.5CuZnSn-0.15Ce brazed joint was decreased by 48.8% compared with the Ag16.5CuZnSn brazed joint. Moreover, the shear strength of the brazed joint decreased with aging time while the shear strength of the AgCuZnSn-xGa-yCe joint was still obviously higher than the Ag16.5CuZnSn joint after a 600 h aging treatment. The fracture type of the Ag16.5CuZnSn-xGa-yCe brazed joints before aging begins ductile and turns slightly brittle during the aging process. Compared to all the results, the Ag16.5CuZnSn-2Ga-0.15Ce brazed joints show the best performance and could satisfy the requirements for cost reduction and long-term use.


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