Part 2: Application of Kanaya–Okayama heat source in modelling micro electron beam welding

Abstract

A three-dimensional finite element model of micro electron beam welding is developed where the Kanaya-Okayama heat source formulated in Part I of this work is used to represent the electron beam. The large number of process variables is grouped into two non-dimensional parameters, namely, Peclet number and relative beam penetration, and their effect is analysed numerically to arrive at the optimum conditions of microwelding. Based on the minimum heat input of the process, the optimum Peclet number is found to be 100, and the beam penetration is twice that of the weld depth. The optimum parameters obtained using the Kanaya-Okayama heat source model are similar to the previous findings using the exponential decay heat source model; however, the predictions of the temperature field in the solid as a result of microwelding are relatively lower in case of the Kanaya-Okayama heat source model because of the differences in distribution of heat into the condensed matter. The lower weld surface temperatures in microwelding using the electron beam suggest significantly less ablation than in laser beams.

Synthesis and generalisation of welding fundamentals to design new welding technologies: Status, challenges and a promising approach

“…Similar analysis has been performed by the author's research group for torque and shear layer thickness in FSW,24 weld penetration in GTAW at high current,31 weld pool morphology at high currents,32 non-linear heat transfer in the wire in GMAW,33 pressures, velocities34 and temperatures in the arc,35 electron beam welding in the micrometre scale36 and ceramic to metal joining 37. A general review of the use of the use of scaling in welding is presented in Ref.…”

Calculation of thermal features in welding and additive manufacturing

“…For some cases, they provide the proper behavior that was missing in previous work, such as width of an isotherm in Regime IV [1]. The case of volumetric heat sources, such as electron beams is analyzed in detail in [42][43][44] The effect of molten metal flow is outside the scope of this paper, and it is often secondary to the other parameters considered here, but not always negligible. The level of difficulty in the treatment increases, but a rigorous scaling approach has been developed in [45], based on [46].…”

Micromanufacturing of composite materials: a review

“…A number of different techniques are reported to join components in microscale. This include microelectronic wire bonding [191,192], solidstate diffusion bonding [193,194], bonding using nanoparticles [195][196][197], diffusion soldering and brazing [198,199], laser microwelding [200][201][202], electron beam microwelding [203,204], resistance microwelding [205,206], adhesive bonding [207], ceramic/ceramic bonding [208][209][210][211], ceramic/metal bonding [40,212], and so on. Figures 11(a) and (b) show typical examples of microjoining of similar and dissimilar materials, respectively.…”