Numerička analiza loma zatezne epruvete sa prslinom u ZUT

Abstract

Numeričkim rešenjima se omogućava istraživanje složenijih problema, uključujući analizu pojedinačnih uticaja, posebno u slučajevima kada izostaju odgovarajući eksperimenti i matematička rešenja usled visoke cene, složenosti problema, itd. U ovom radu se razmatra numeričko modeliranje i analiza ponašanja loma zavarenih zateznih epruveta sa prslinom u ZUT, na primer, uticaj heterogenosti zavarenog spoja na raspodelu napona i deformacija ispred vrha prsline, kao i uzroci pojave loma. Analizirana su dva slučaja: vrh prsline lociran u finozrnom ZUT i vrh prsline lociran u grubozrnom ZUT. Eksperimentalna istraživanja, u oba slučaja, su pokazala dejstvo prepreke mismečinga zavarenog spoja, nakon inicijalnog širenja prsline u finozrnom ili u grubozrnom ZT, što je prouzrokovalo skretanje rasta prsline u oblasti duktilnijeg osnovnog materijala, čime se smanjila i brzina rasta prsline. U ovom članku su opisana razmatranja ovakvog ponašanja uz primenu numeričke simulacije eksperimenta. .

Numerical solutions enable investigation of complex problems, including analysis of various influences, especially in cases when experimental research and mathematical solutions are not appropriate, such as high price, problem complexity, etc. In this article, numerical modeling and analysis is presented, concerning fracture behavior of HAZ cracked welded tensile specimens i.e. the influence of welded joint heterogeneity on the distribution of stress and strain in front of the crack tip and the reasons causing failure. Two cases are analyzed: crack tip located in fine-grained HAZ and crack tip located in coarse-grained HAZ. Experimental research in both cases exhibited that the barrier act of welded joint mismatch, after the initial propagation of crack in fine-grained or coarse-grained HAZ, has brought to a turn of crack propagation into more ductile base metal, thus decreasing the crack propagating speed. The article brings some observations regarding such behavior by applying numerical simulations to the experiment. .