Microstructure of austenitic stainless steel is primarily monophasic, i.e. austenitic. However, precipitation of the δ-ferrite in the austenite matrix is possible depending on the chemical composition of steel. δ-Ferrite is stable on room temperature but it transforms into σ-phase, carbides and austenite during heat treatment. In this work, the results of analysis of influence of temperature and time on decomposition of δ-ferrite are presented. Magnetic induction method, microstructure and hardness analyses were used for testing the degree of decomposition of the δ-ferrite. Analysis of results showed that increase in temperature and time increases the degree of decomposition of δ-ferrite.

In this paper, the room temperature mechanical properties, as well as the microstructure of HK 30 Nb steel, were tested in the initial as-cast and solution annealed condition. Results show that tensile properties after the solution annealing have a slightly lower value than as-cast samples. Microstructural analysis of samples after solution annealing showed dissolution of primary carbides present in the initial as-cast condition. The morphology and composition of carbides were changed during a solution annealing. Analysis of microstructure was done by optical microscopy (OM) and scanning electron microscope (SEM), whereas hardness and tensile tests were performed for characterization of mechanical properties.

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In most cases an addition of inoculants to molten cast iron is advisable and even necessary to produce good-quality castings. The mechanical properties and machinability of cast iron with nodular graphite greatly depend on the formation of graphite and the matrix microstructure and both are significantly influenced by the inoculation treatment. The mechanism of inoculation, the influence of the inoculation method and the amount of added inoculants are presented. Keywords: ductile iron, inoculation, microstructure, graphite, metallic matrix V ve~ini primerov je dodatek modifikatorjev staljenemu livnemu`elezu priporo~ljiv in celo potreben za izdelavo dobrih ulitkov. Mehanske lastnosti in obdelovalnost litega`eleza z nodularnim grafitom so mo~no odvisne od oblike grafita in od mikrostrukture osnove, na oboje pa mo~no vpliva obdelava z modifikatorji. Predstavljen je mehanizem modifikacije, vpliv metode modifikacije in vpliv koli~ine dodanega modifikatorja.

The Au-Ge alloy is useful for bonding applications in microelectronic and optoelectronic packages. Also, recent investigations show that Au-Ge system could present a lead-free solder candidate. The results of characterization of the eutectic alloy from binary Au-Ge system are presented in this paper. Experimental research was done using thermal analysis (differential thermal analysis, DTA) and structural investigation by light optic microscopy (LOM) and scanning electron microscopy with EDS (SEM-EDS). The eutectic temperature of 359 °C was detected using thermal analysis, while eutectic structure was confirmed using microstructural analysis. Obtained results were compared with recent literature references and good mutual agreement was noticed.