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In the period after 1945 until 1990 Croatia had several metallurgical companies and acceptable production. In ex-Yugoslavia Craotia was the only manufacturer of seamless pipes among 34 countries in the world Steelwork Sisak, with an annual production of about 140.000 t. It was an important manufacturer of welded pipes of over 200.000 t per year, strip and billets till 250.000 t/y, in addition to cold processing (drawing, pilgering) about 10.000 t per year. Steel production (2 Siemens – Martin furnaces) and 1 electric furnace together with 2 high furnaces (of 150 m3 production till 200.000 t/y was about 360.000 t per year, and up to 850.000 t coke per year were produced in Koksara / Coke Plant Bakar. (Note: Per year in 1990 until 2014 this plants were form down and put out operation). In monograph Đ. Tadić “Steeworks Sisak, Company of steel and lifetime “, gave the period (quote) “lifetime one Company in developing“ 1956 – 1989 y. Contents are from published selected Articles from Journal of Steel work Sisak “ Vjesnik Željezare“.

Minutes of the Meeting of the Editorial Board of the Journal Metalurgija, held on 25 June, 2018 in the Hotel Ivan – Solaris, Šibenik with the beginning at 4 PM, Hall Žirje.

The paper proposes a variant for solving the problem of reduction of longitudinal residual stresses in near-root region of a circumferential welded joint of section of steam pipeline by FEM simulation of the stress-strain state of repaired section of a circumferential weld in the zone of lack of root penetration on a thin-wall shell of 89 mm diameter and 6 mm wall thickness from steel 20. The result of solving the problem is total distribution of stresses and residual plastic deformations in the repaired zone.

The main tendency towards the development of the methods for predicting long-time data on of metallic materials is to derive the correlation relationships, which should be as general as possible. This paper presents the verification of the fact that a sufficiently accurate estimation of the peculiarities of the portions of experimental diagrams and generalization of this information can be of great importance for a considerable progress in the prediction.

Ti-Nb alloys are of a large potential for industrial, as well as biomedical utilisation. Oxygen content in the alloy is a parameter infl uencing its properties and cannot be neglected. The main focus of this paper is on observation of infl uence of annealing time on oxygen content in the structure of Ti – 20,7 (at.)% Nb alloy. Four groups of the samples were annealed at the temperature of 800 °C from 15 to 60 minutes with 15 min. step. As it was proven by the analysis, the oxygen content increased with increasing annealing time. Moreover, microhardness measurements showed increasing trend of HV microhardness value with increasing oxygen content. Web of Science 53 2 188 186

Mechanical properties of a steam tube made of CrMo creep resistant steel are analysed in this contribution after up to 2, 6•105 hours service life in creep conditions at temperature 530 °C and calculated stress level in the tube wall 46, 5 MPa. During service life there were in the steel gradual micro structure changes, fi rst pearlite spheroidization, precipitation, coaugulation and precipitate coarsening. Nevertheless the strength and deformation properties of the steel (Re, Rm, A5, Z), and the resistance to brittle fracture and the creep strength limit, were near to unchanged after 2, 1•105 hours in service. The steam tube is now in service more than 2, 6•105 h.

The main purpose of this paper is to give a mathematical description of flow stress of examined aluminium alloys on the basis of upsetting tests perdormed in a servohydraulic plastomer. Deformation curves have been described by means of the Sellars-Tegart-Garofalo equation, with the aid of linear regression analysis by the neural network method implemented in the NEUREX program., Glavni cilj članka je dati matematički opis toka naprezanja ispitivanih aluminijskih legura na temelju testa opterećenja proveden na servohidrauličkom plastomeru. Krivulje deformacije su opisane pomoću Sellars-Tegart-Garofalo jednadžbe, uz podršku linearnih regresionih analiza te metodom neuralne mreže ostvarene u NEUREX programu.

The article gives a review of selected new technologies of materials forming. That is selected 10 procedures, first, high pressure torsion processing, at the end, metal injection molding. All the new procedures have good performance and in the future for expect more the application in industry. Članak daje osvrt odabranih novih tehnologija u oblikovanju deformiranjem materijala. To je odabranih 10 postupaka, prvi, visokotlačna torziona obradba i na kraju, lijevačko injektiranje metala. Svi novi postupci imaju dobre karakteristike i u budućnosti za očekivati veću primjenu u undustriji. Web of Science 49 3 174 169

Da bi opstao i zadržao prednost izradbe bešavnih cijevi u odnosu na suvremene valjaonice, kod pilger postupka treba povećati produktivnost, smanjiti troškove prerade i posebice poboljšati kakvoću i površinu cijevi. U članku se daje mogućnost modernizacije pilger stana (pogona, kućišta, posmaka cijevnice, itd.).