The Energy Spectrum Fluctuation Size Effect Study of the Holes in the Crystal - TiAl Crack Propagation

Abstract

The paper studied the sized effect for the system energy spectrum wave phenomenon in the process of crack propagation for the single crystal gamma - TiAl alloy of the hole defects. With the ways of molecular dynamics method and used the embedded atom potential method, The different hole size （ R=1Ã… ã€2Ã… 〠3Ã… ） influenced the system energy change (curve a, b, c)in the process of the crack propagations combined with atomic path chart were analysised. The results indicated that the three energy evolution curve models showed the fluctuating phenomenons; Three curves had the same change trend before t = 125 ps, the total energy showed a trend of increased with the Internal atomic fuel movement , and the kinetic energy and potential energy increased. With load continued, The curve a, b, c appeared the low energy at t = 172 ps, t = 188 ps, t = 186 ps respectively, and the energy values is 648483.4 E/ev, 647674.85 E/ev, 646124.39 E/ev respectively; The hole effect model of the different holes size R=1Ã… 〠3Ã… appeared The main and second cracks convergence phenomenon at t = 560Ps, t = 732 ps respectively, and the energy attained secondary low value 648671.12 E/ev, 645719.59 E/ev respectively; On the whole, the curve c is stable relatively, the fluctuation amplitude was small, and the overall energy was the minimum, and the curve a and b fluctuations was bigger.