The Experts below are selected from a list of 41085 Experts worldwide ranked by ideXlab platform
Di Zhao - One of the best experts on this subject based on the ideXlab platform.
-
dynamic observation of interfacial imc evolution and Fracture Mechanism of sn2 5ag0 7cu0 1re cu lead free solder joints during isothermal aging
Materials, 2020Co-Authors: Keke Zhang, Di Zhao, Chenxiang Yin, Fupeng HuoAbstract:Dynamic observation of the microstructure evolution of Sn2.5Ag0.7Cu0.1RE/Cu solder joints and the relationship between the interfacial intermetallic compound (IMC) and the mechanical properties of the solder joints were investigated during isothermal aging. The results showed that the original single scallop-type Cu6Sn5 IMC gradually evolved into a planar double-layer IMC consisting of Cu6Sn5 and Cu3Sn IMCs with isothermal aging. In particular, the Cu3Sn IMC grew towards the Cu substrate and the solder seam sides; growth toward the Cu substrate side was dominant during the isothermal aging process. The growth of Cu3Sn IMC depended on the accumulated time at a certain temperature, where the growth rate of Cu3Sn was higher than that of Cu6Sn5. Additionally, the growth of the interfacial IMC was mainly controlled by bulk diffusion Mechanism, where the activation energies of Cu6Sn5 and Cu3Sn were 74.7 and 86.6 kJ/mol, respectively. The growth rate of Cu3Sn was slightly faster than that of Cu6Sn5 during isothermal aging. With increasing isothermal aging time, the shear strength of the solder joints decreased and showed a linear relationship with the thickness of Cu3Sn. The Fracture Mechanism of the solder joints changed from ductile Fracture to brittle Fracture, and the Fracture pathway transferred from the solder seam to the interfacial IMC layer.
Fupeng Huo - One of the best experts on this subject based on the ideXlab platform.
-
dynamic observation of interfacial imc evolution and Fracture Mechanism of sn2 5ag0 7cu0 1re cu lead free solder joints during isothermal aging
Materials, 2020Co-Authors: Keke Zhang, Di Zhao, Chenxiang Yin, Fupeng HuoAbstract:Dynamic observation of the microstructure evolution of Sn2.5Ag0.7Cu0.1RE/Cu solder joints and the relationship between the interfacial intermetallic compound (IMC) and the mechanical properties of the solder joints were investigated during isothermal aging. The results showed that the original single scallop-type Cu6Sn5 IMC gradually evolved into a planar double-layer IMC consisting of Cu6Sn5 and Cu3Sn IMCs with isothermal aging. In particular, the Cu3Sn IMC grew towards the Cu substrate and the solder seam sides; growth toward the Cu substrate side was dominant during the isothermal aging process. The growth of Cu3Sn IMC depended on the accumulated time at a certain temperature, where the growth rate of Cu3Sn was higher than that of Cu6Sn5. Additionally, the growth of the interfacial IMC was mainly controlled by bulk diffusion Mechanism, where the activation energies of Cu6Sn5 and Cu3Sn were 74.7 and 86.6 kJ/mol, respectively. The growth rate of Cu3Sn was slightly faster than that of Cu6Sn5 during isothermal aging. With increasing isothermal aging time, the shear strength of the solder joints decreased and showed a linear relationship with the thickness of Cu3Sn. The Fracture Mechanism of the solder joints changed from ductile Fracture to brittle Fracture, and the Fracture pathway transferred from the solder seam to the interfacial IMC layer.
Keke Zhang - One of the best experts on this subject based on the ideXlab platform.
-
dynamic observation of interfacial imc evolution and Fracture Mechanism of sn2 5ag0 7cu0 1re cu lead free solder joints during isothermal aging
Materials, 2020Co-Authors: Keke Zhang, Di Zhao, Chenxiang Yin, Fupeng HuoAbstract:Dynamic observation of the microstructure evolution of Sn2.5Ag0.7Cu0.1RE/Cu solder joints and the relationship between the interfacial intermetallic compound (IMC) and the mechanical properties of the solder joints were investigated during isothermal aging. The results showed that the original single scallop-type Cu6Sn5 IMC gradually evolved into a planar double-layer IMC consisting of Cu6Sn5 and Cu3Sn IMCs with isothermal aging. In particular, the Cu3Sn IMC grew towards the Cu substrate and the solder seam sides; growth toward the Cu substrate side was dominant during the isothermal aging process. The growth of Cu3Sn IMC depended on the accumulated time at a certain temperature, where the growth rate of Cu3Sn was higher than that of Cu6Sn5. Additionally, the growth of the interfacial IMC was mainly controlled by bulk diffusion Mechanism, where the activation energies of Cu6Sn5 and Cu3Sn were 74.7 and 86.6 kJ/mol, respectively. The growth rate of Cu3Sn was slightly faster than that of Cu6Sn5 during isothermal aging. With increasing isothermal aging time, the shear strength of the solder joints decreased and showed a linear relationship with the thickness of Cu3Sn. The Fracture Mechanism of the solder joints changed from ductile Fracture to brittle Fracture, and the Fracture pathway transferred from the solder seam to the interfacial IMC layer.
-
study on Fracture Mechanism of the aged sn2 5ag0 7cu0 1re cu soldering joint with external energy
International Conference on Electronic Packaging Technology, 2014Co-Authors: Xingdong Guo, Keke ZhangAbstract:With ultrasonic vibration and electric field, Sn2.5Ag0.7Cu0.1RE/Cu solder was experimented. Mechanical property and Fracture Mechanism of aged joint were researched with the modern physical and chemical detection methods. The results show that when ultrasonic power is 88w, time is 60s, electric field is 2 kV/cm, aging treatment temperature is 150°C, aging time is 200h, the shear strength of soldering joint can achieve 21.54 MPa, which is 47.5% higher than that of traditional soldering. The brittle Fracture of traditional soldering joint occurred in the IMC layer. While mixed-Fracture composed of granular IMC phase and "parabola" shear dimple of brittle and ductile was observed in the interface of the soldering joint with ultrasonic vibration. Particularly, ductile Fracture composed of large sized "parabola" shear dimple was detected in the soldering seam of the aged joint with ultrasonic vibration and electric field.
Guoqiang Liu - One of the best experts on this subject based on the ideXlab platform.
-
effects of pre treatments on mechanical properties and Fracture Mechanism of a nickel based superalloy
Materials Science and Engineering A-structural Materials Properties Microstructure and Processing, 2017Co-Authors: Y C Lin, Mingsong Chen, Guoqiang LiuAbstract:Abstract The effects of pre-treatments (interrupted and direct water-cooled methods) on the microstructural evolution, mechanical properties and Fracture Mechanism of a nickel-based superalloy are studied. It is found that the mechanical properties and Fracture Mechanism of the studied superalloy are sensitive to pre-treatment. The number and size of γ′′(Ni 3 Nb) and γ′(Ni 3 Al) phases rapidly decrease with the increase of interrupted temperature. For the interrupted water-cooled superalloy, when the interrupted temperature is below 705 °C, the microhardness is relatively high due to the precipitation of the γ′′and γ′ phases. However, when the interrupted temperature is increased from 705 °C to 780 °C, the microhardness dramatically decreases. Meanwhile, the yield strength and ultimate tensile strength also rapidly decrease, while the elongation to Fracture sharply increases. Additionally, the Fracture Mechanism of the studied superalloy transforms from brittle intergranular Fracture to ductile transgranular Fracture with the increase of interrupted temperature. Compared with the direct water-cooled superalloy, the microhardness, yield strength and ultimate tensile strength of the interrupted water-cooled superalloy are greatly improved when the interrupted temperature is below 780 °C.
Atsushi Sugeta - One of the best experts on this subject based on the ideXlab platform.
-
fatigue Fracture Mechanism on friction stir spot welded joints using 300 mpa class automobile steel sheets under constant and variable force amplitude
Procedia Materials Science, 2014Co-Authors: Sutep Joyaka, Atsushi Sugeta, Yuki Ogawa, Yufeng Sun, Hidetoshi FujiiAbstract:Abstract The authors have shown an approach to evaluate the fatigue Fracture Mechanism of cross-tension specimen welded using low carbon steel by friction stir spot welding (FSSW) with the focus on fatigue crack behaviour. Results show that, the fatigue limit of FSSW specimen was very low comparing to the tensile force of base metal and FSSW joint itself. The fatigue cracks initiated near the interface between two thin steel sheets under constant force amplitude conditions were observed in detail by the 3- dimensional observation method. The typical morphologies of 3-dimension were observed with constant low force amplitude level at 0.19 kN and high force amplitude level at 0.49 kN of each fatigue life. It is clear that a main crack initiated at the end of slit and Fracture modes were independent on force amplitude level. And, FSSW joint used in this study requires the large and few number of cyclic loading to initiate the fatigue crack under low and high force amplitude level, respectively. Moreover, an evaluation method for the cumulative fatigue damage under variable force amplitude conditions was observed. The results show that, this method can be used to evaluate FSSW joint efficiency in automotive industry and other practical applications.
-
3 dimensional observation of the interior Fracture Mechanism and establishment of cumulative fatigue damage evaluation on spot welded joints using 590 mpa class steel
International Journal of Fatigue, 2013Co-Authors: Ryota Tanegashima, Hiroyuki Akebono, Masahiko Kato, Atsushi SugetaAbstract:Abstract To investigate the fatigue Fracture Mechanism in spot welded joints using a 590 MPa-class base metal, fatigue tests were conducted under constant loading conditions. In this study, three dimensional observation was made on the propagation behavior of fatigue cracks initiating at the edge of the slit between sheets. Moreover, an evaluation method of the fatigue life was proposed for random loading conditions. Since the mean load obviously affected the fatigue life of the spot welded joints, the proposed evaluation method was applied to account for this load effect. The proposed evaluation method satisfied the application range in the automobile industry. Therefore, it is thought that the proposed method is suitable for practical applications.
