The Experts below are selected from a list of 57 Experts worldwide ranked by ideXlab platform

E J Mittemeijer - One of the best experts on this subject based on the ideXlab platform.

  • characterization of the reaction process in diffusion soldered cu in 48 at sn cu joints
    Materials Chemistry and Physics, 2003
    Co-Authors: S Sommadossi, W Gust, E J Mittemeijer
    Abstract:

    Abstract This work describes a Pb-free solder alternative for the interconnection technology and its implementation in a diffusion soldering technique: In–48 at.% Sn solder (eutectic alloy), with a melting point of 120 °C. The system proposed has the advantages of both traditional soldering and diffusion bonding, i.e., good joint filling, High Service Temperature, and good mechanical properties. The diffusion reaction processes in Cu/In–48 at.% Sn/Cu joints were investigated between 180 and 400 °C. Electron microprobe analysis revealed the presence of one or two intermetallic layers in the interconnection zone: a layer of the η phase below 200 °C, and layers of the η and ζ phases above 200 °C. The η and ζ phases form through a solid–liquid and a solid–solid diffusion reaction, respectively. Below 200 °C the η phase exhibits two different morphologies: large coarse grains at the η/(originally liquid)In–48 at.% Sn interface and a fine-grained region at the Cu/η interface. The thickness of the ζ layer shows a constant growth rate (linear growth) at constant Temperature. The Temperature dependence of the growth rate constant of the ζ layer is described by an Arrhenius relationship with an activation energy equal to 121 kJ/mol and a pre-exponential factor of about 57 m/s.

  • novel ni al ni diffusion soldered joints for High Temperature applications
    EUROMAT 99 6th European Congress on Advanced Materials and Processes, 2000
    Co-Authors: P K Khanna, S Sommadossi, W Gust, E J Mittemeijer, G A Lopez, E Bielanska, P Zieba, L S Chang
    Abstract:

    A novel environment-friendly process based on diffusion soldering for Ni/Ni interconnections using Al as the joint material is developed. The interconnections formed can be thermally stable up to 1133-1638 °C due to the High melting point of the intermetallics formed. This feature is a very important requirement which is not possible to satisfy using conventional soldering process. This joints find application in High Service Temperature sensors and contacts like in hot plates and between resistive heaters and electrical leads.

S Sommadossi - One of the best experts on this subject based on the ideXlab platform.

  • characterization of the reaction process in diffusion soldered cu in 48 at sn cu joints
    Materials Chemistry and Physics, 2003
    Co-Authors: S Sommadossi, W Gust, E J Mittemeijer
    Abstract:

    Abstract This work describes a Pb-free solder alternative for the interconnection technology and its implementation in a diffusion soldering technique: In–48 at.% Sn solder (eutectic alloy), with a melting point of 120 °C. The system proposed has the advantages of both traditional soldering and diffusion bonding, i.e., good joint filling, High Service Temperature, and good mechanical properties. The diffusion reaction processes in Cu/In–48 at.% Sn/Cu joints were investigated between 180 and 400 °C. Electron microprobe analysis revealed the presence of one or two intermetallic layers in the interconnection zone: a layer of the η phase below 200 °C, and layers of the η and ζ phases above 200 °C. The η and ζ phases form through a solid–liquid and a solid–solid diffusion reaction, respectively. Below 200 °C the η phase exhibits two different morphologies: large coarse grains at the η/(originally liquid)In–48 at.% Sn interface and a fine-grained region at the Cu/η interface. The thickness of the ζ layer shows a constant growth rate (linear growth) at constant Temperature. The Temperature dependence of the growth rate constant of the ζ layer is described by an Arrhenius relationship with an activation energy equal to 121 kJ/mol and a pre-exponential factor of about 57 m/s.

  • novel ni al ni diffusion soldered joints for High Temperature applications
    EUROMAT 99 6th European Congress on Advanced Materials and Processes, 2000
    Co-Authors: P K Khanna, S Sommadossi, W Gust, E J Mittemeijer, G A Lopez, E Bielanska, P Zieba, L S Chang
    Abstract:

    A novel environment-friendly process based on diffusion soldering for Ni/Ni interconnections using Al as the joint material is developed. The interconnections formed can be thermally stable up to 1133-1638 °C due to the High melting point of the intermetallics formed. This feature is a very important requirement which is not possible to satisfy using conventional soldering process. This joints find application in High Service Temperature sensors and contacts like in hot plates and between resistive heaters and electrical leads.

Jinwen Zhang - One of the best experts on this subject based on the ideXlab platform.

  • A Self-Healable High Glass Transition Temperature Bioepoxy Material Based on Vitrimer Chemistry
    Macromolecules, 2018
    Co-Authors: Shuai Zhang, Yuzhan Li, Xiaoning Yang, Liwei Wang, Jinwen Zhang
    Abstract:

    The design of High glass transition Temperature (Tg) thermoset materials with considerable reparability is a challenge. In this study, a novel biobased triepoxy (TEP) is synthesized and cured with an anhydride monomer in the presence of zinc catalyst. The cured TEP exhibits a High Tg (187 °C) and comparable strength and modulus to the cured bisphenol A epoxy. By adopting the vitrimer chemistry, the cross-linked polymer materials are imparted significant stress relaxation and reparability via dynamic transesterification. It is noted that the reparability is closely related to the repairing Temperature, external force, catalyst content, and the magnitude of rubbery modulus of the sample. The width of the crack from the cured TEP can be efficiently repaired within 10 min. This work introduces the first High-Tg biobased epoxy material with excellent reparability and provides a valuable method for the design of High-Tg self-healing materials suitable for High Service Temperature.

  • mild chemical recycling of aerospace fiber epoxy composite wastes and utilization of the decomposed resin
    Polymer Degradation and Stability, 2017
    Co-Authors: Tuan Liu, Meng Zhang, Xiaolong Guo, Chengyun Liu, Tian Liu, Junna Xin, Jinwen Zhang
    Abstract:

    Carbon fiber reinforced polymers (CFRPs) with High Tg (>200 °C) are indispensable for aerospace industry where High Service Temperature is required. Chemical recycling of the matrix polymers for these CFRP composites is more difficult than that of their low Tg analogues. In this work, an efficient approach for mild chemical recycling of CFRP with a Tg of ∼210 °C was developed using a ZnCl2/ethanol catalyst system. The High efficiency of ZnCl2/ethanol was attributed to the strong coordination effect of ZnCl2 with the C-N bonds and the strong swelling ability of ethanol, which worked together to break down the chemical bonds of the cross-linked polymer. Also, mild degradation Temperature (<200 °C) imparted little damage to the recovered fibers. The decomposed matrix polymer (DMP) was in the oligomer form and contained multifunctional reactive groups. When DMP was used as a reactive ingredient and added up to 15 wt% to the preparation of new epoxy materials, the resulting cross-linked polymers could still retain the High strength and modulus compared to the neat polymer without addition of DMP.

W Gust - One of the best experts on this subject based on the ideXlab platform.

  • characterization of the reaction process in diffusion soldered cu in 48 at sn cu joints
    Materials Chemistry and Physics, 2003
    Co-Authors: S Sommadossi, W Gust, E J Mittemeijer
    Abstract:

    Abstract This work describes a Pb-free solder alternative for the interconnection technology and its implementation in a diffusion soldering technique: In–48 at.% Sn solder (eutectic alloy), with a melting point of 120 °C. The system proposed has the advantages of both traditional soldering and diffusion bonding, i.e., good joint filling, High Service Temperature, and good mechanical properties. The diffusion reaction processes in Cu/In–48 at.% Sn/Cu joints were investigated between 180 and 400 °C. Electron microprobe analysis revealed the presence of one or two intermetallic layers in the interconnection zone: a layer of the η phase below 200 °C, and layers of the η and ζ phases above 200 °C. The η and ζ phases form through a solid–liquid and a solid–solid diffusion reaction, respectively. Below 200 °C the η phase exhibits two different morphologies: large coarse grains at the η/(originally liquid)In–48 at.% Sn interface and a fine-grained region at the Cu/η interface. The thickness of the ζ layer shows a constant growth rate (linear growth) at constant Temperature. The Temperature dependence of the growth rate constant of the ζ layer is described by an Arrhenius relationship with an activation energy equal to 121 kJ/mol and a pre-exponential factor of about 57 m/s.

  • novel ni al ni diffusion soldered joints for High Temperature applications
    EUROMAT 99 6th European Congress on Advanced Materials and Processes, 2000
    Co-Authors: P K Khanna, S Sommadossi, W Gust, E J Mittemeijer, G A Lopez, E Bielanska, P Zieba, L S Chang
    Abstract:

    A novel environment-friendly process based on diffusion soldering for Ni/Ni interconnections using Al as the joint material is developed. The interconnections formed can be thermally stable up to 1133-1638 °C due to the High melting point of the intermetallics formed. This feature is a very important requirement which is not possible to satisfy using conventional soldering process. This joints find application in High Service Temperature sensors and contacts like in hot plates and between resistive heaters and electrical leads.

Henry A Sodano - One of the best experts on this subject based on the ideXlab platform.

  • High Service Temperature self mendable thermosets networked by isocyanurate rings
    Polymer, 2017
    Co-Authors: Lisha Zhang, Florian Jule, Henry A Sodano
    Abstract:

    Abstract A new mending chemistry exhibiting stability at extreme Temperatures and holding mechanical properties as well as mechanical stability comparable to widely used engineering plastics is reported here. This mendable thermoset polymer is synthesized using commodity reactants through the formation of an isocyanurate-oxazolidone network which exhibit a High Service Temperature as shown by their Tg of 270 °C and Td of 365 °C. We demonstrate that this network polymer is repeatedly self-mendable in the presence of a macroscopic crack, yielding considerable recovery of the polymer's strength after thermal annealing. This self-mending behavior is derived from a High density of mechano-responsive isocyanurate rings which are introduced as cross-links in the network. After mechanically initiated cycloreversion, the recovery of isocyanurate rings in a solid state is thermally initiated. This research is the first demonstration of an isocyanurate ring as a repairing moiety. We developed a new class of intrinsic self-mendable polymers withstanding High Temperatures, which will greatly impact the application of thermoset polymers in the field of structural laminates and electronics packaging.