Numerical simulation of welding distortions at complex structures

U diplomskom radu je detaljno proučeno zavarivanja nehrđajućeg čelika s posebnim naglaskom na njegove deformacije u stvarnosti i na numeričkoj simulaciji. Prvo slijedi jedan kratki uvod u povijest nehrđajućih čelika, a zatim se čitatelj upoznaje s njihovom podjelom po mikrostrukturi, gdje se naglasak stavlja na njihovu primjenu, svojstva i zavarljivost. Također, obrađen je i postupak zavarivanja MIG/MAG gdje se čitatelj susreće s potrebnim elementarnim stvarima. Zatim se obrađuju deformacije koje se javljaju tijekom zavarivanja, njihova podjela te neki od načina njihovog sprječavanja. U zadnjem dijelu rada obrađena je metoda konačnih elemenata koja je nužno potrebna za izvedbu numeričke simulacije u programskom paketu „Visual Environment.“ Eksperimentalni dio rada sastoji se od dva dijela: stvarno (realno) i simulirano zavarivanje. Stvarno zavarivanje provedeno je u Laboratoriju za zavarivanje na Fakultetu strojarstva i brodogradnje gdje se zavarivala složena konstrukcija od austenitnog čelika. Sav postupak od pripreme spoja, opreme, dodatnog materijala postepeno je objašnjen. Simulirano zavarivanje provedeno je programskom paketu Visual Environment. Svi koraci numeričke simulacije su detaljno objašnjeni. U zadnjem dijelu eksperimentalnog rada, obrazloženi su dobiveni rezultati.In the masterwork, stainless steel welding was studied in detail, with special emphasis on its deformation in reality and numerical simulation. First, there is an introduction to the history of stainless steel, and then the reader gets acquainted with their microstructural division, where the emphasis is placed on their application, properties, and weldability. Also, the MIG/MAG procedure of welding was processed, where the reader acquainted the necessary elementary things. Afterward, there is processing of deformation, which will occur during the welding, their divisions and some of their ways of preventing. The final part is processed the finite element method, which is indispensable for performing numerical simulation in the „Visual Environment“ program package. The experimental part consists of two parts: real welding and simulation welding. Actual welding was processed at the Welding Laboratory at the Faculty of Mechanical Engineering and Naval Architecture, where a complex austenitic steel structure was welded. All the process of preparing the compound, the equipment, the additional material has been explained in detail. Simulated welding was processed in the Visual Environment program package. All steps of numerical simulation are explained in detail. In the last part of the experimental work, the results obtained are commented