Influence of heat treatment at wire and arc additive manufacturing on mechanical properties of duplex steel

Ovaj diplomski rad sastoji se od dva dijela , teorijskog i eksperimentalnog. U teorijskom dijelu rada opisana je aditivna proizvodnja u poseban naglasak na aditivnu proizvodnju električnim lukom i žicom. Posebna pažnja dana je anizotropnosti materijala nakon aditivne proizvodnje, kao i toplinskoj obradi kao metodi smanjenja anizotropnosti. Zbog kompleksnosti dupleks strukture opisan je utjecaj pojedinih legirnih elemenata na mikrostrukturu dupleksa te su opisana svojstva dupleksa 2205. U eksperimentalnom dijelu rada izrađen je jedan novi zid WAAM postupkom te je korišten i prethodno izrađen zid. Na dijelu uzorka iz prethodno izrađenog zida obavljena su ispitivanja kemijskog sastava po poprečnom presjeku, dok je ostatak uzorka većinom korišten za statički vlačni pokus i ispitivanje tvrdoće. Dio uzorka bio je podvrgnut toplinskoj obradi kako bi se vidjeli utjecaji iste na mikrostrukturu i mehanička svojstva. Novi zid je služio samo za izradu epruveta za statički vlačni pokus te je isto tako dio epruveta podvrgnut toplinskoj obradi. Statički vlačni pokus provođen je u smjeru izrade zida i okomito na smjer izrade.This master thesis consists of two parts, theoretical and experimental The theoretical part of the thesis describes additive manufacturing with special emphasis on Wire + Arc Additive Manufacturing. Special attention is given to the anisotropy of the material after additive production, as well as heat treatment as a method of reducing anisotropy. Due to the complexity of the duplex structure, the influence of individual alloying elements on the microstructure of the duplex is described. Properties of duplex 2205 are described as well. In the experimental part of the thesis, a new wall was made using the WAAM, there was also made use of the previously created wall. Part of the samples from the previously made wall was used for testing chemical composition over the cross-section of the wall. The rest of the samples were mostly used for static tensile testing and hardness testing. Part of the samples, half of them, was subjected to heat treatment to see the effect on the microstructure and mechanical properties. The new wall was used only to make tensile test specimens, part of the specimens was subjected to heat treatment. Static tensile testing was carried out in the build direction of the wall and perpendicular to the build direction