Papers by Author: Evgeny E. Glickman

Abstract: The models of liquid –metal embrittlement (LME) which explore the concept of fast stress/strain induced liquid phase diffusion as the major factor responsible for acceleration of subcritical cracks are overviewed and refined. The models are used for further analysis of several focus issues in the LME kinetics.

Abstract: Spreading of liquid and solid Ga over the surface of thin polycrystalline Ag film is accompanied by fast penetration of Ga through the film. The penetration process between +60°C and –10°C has likely a common mechanism with the spreading. The activation energies of the process responsible for spreading/penetration are EL = 0.3±0.05 eV and ES = 0.5±0.1 eV for liquid and solid Ga, respectively. The common mechanism is attributed to grain boundary (GB) grooving with diffusion of Ag out of the groove either via liquid Ga or along GBs in solid Ga. A possible formation of intermetallic compound between Ag and Ga is considered as the secondary process, which does not control the kinetics. The model reproduces the spreading/penetration rates that are observed, and gives reasonable estimates of the experimental activation energies ES and EL.

Abstract: Thermodynamic conditions for spontaneous grain boundary wetting (GBW) and stress driven liquid metal embrittlement (LME) are related to each other. Kinetic mechanism responsible for fast GB penetration (GBP) under small stress is described. Dissolution–condensation mechanism of LME and linear fracture mechanics for calculation of crack profile are applied to the classical system “Al-liquid Ga”. The results tend to support the idea that the recently observed fast linear penetration of Ga along 150° tilt <110> GB of Al should be considered as propagation of LME crack under small residual stress rather than as spontaneous GBW. With the residual tensile stress σ≈ 0.5MPa acting normal to the GB plane, all major findings reported for this model system are explained in semi quantitative way assuming that GB spreading coefficient is extremely small by its absolute value, i.e. that the system is near the threshold of spontaneous GBW.