This paper presents an experimental investigation into the effect of nanosilica addition to porosity and capillary absorption of concrete. Three concrete mixtures 0%, 2%, and 4% nanosilicaby weight of cementweretested.The procedure described in ASTM C642-06 was used to determine the total volume of permeable voids.Water absorption and the rate of w...

By Adnan Mujkanovic, Anesa Ključanin, Marina Jovanović, Amel Zahirović, Amna Karić, Nevzet Merdić

Particle size distribution measurements were performed on ground granulated blastfurnace slag by laser diffraction with the powder dispersed in distilled water with sodium hexametaphosphate used as dispersing agent, as well as in pure distilled water and propan-2-ol. Two samples of slag with Blaine fineness 4700 cm2 /g and5500 cm2 /g were tested.Th...

By Adnan Mujkanovic, Marina Jovanović, Amel Zahirović, Mustafa Hadžalić, Nevzet Merdić

The paper examined the changes in properties of conventional castables composed of a mixture of calcium-aluminate cement and chamotte caused by changes in the particle size distribution. Properties of castable with 20 % cement and „as received“ chamotte were compared with castableofparticle size distribution adapted to the calculated di...

By Marina Jovanović, Adnan Mujkanovic

In this paper, the influence of Na2SiO3 /NaOH ratio on the compressive strength of fly ash - based geopolymers was tested. The fly ash from thermal power plant Stanari near Doboj, BiH is used.The ratio of alkali activator to fly ash (AA / FA ratio) was constant in all samples and it was 0.8. A 12M NaOH solution was used. The heat treatment temperat...

By Nadira Bušatlić, Ilhan Bušatlić, Nevzet Merdić, Dženana Smajić-Terzić

In order to reduce the harmful effects of exhaust gases on the environment, as of January 1, 2017, at all stations for technical inspection of vehicles, during the regular technical inspection of vehicles, the contents of motor vehicle exhausts are also carried out - EKO test. According to the Rulebook on Exhaust Gas Testing of Motor Vehicles (ECO ...

By Dragana Agić, Fuad Klisura

Many researches are done for finding various ways of improving steel properties, since it's the most used material in the world. Instead of using high-alloyed steels, which are expensive, microalloying of carbon steels that will retain equal properties is an efficient replacement. For this research it was tested melts of low-carbon steel grade SAE ...

By Aida Imamović, Adna Puljić, Omer Kablar

Proper calibration of the device is important to prevent potential sources of error, which ensures that the test results most effectively represent the value of the sample being tested. In microhardness testing, the loading force does not exceed 1.96 N. The test surface requires a more complex metallographic preparation, and the smaller the injecti...

By Edib Horoz, Belma Fakić, Adisa Burić, Mirsada Oruč

Dual phase steels are low carbon steels which are thermo-mechanically processed to getting better formability and toughness than ferrite-perlite steels with similar tensile strength. The microstructure of these steels consisting of a ferrite matrix with hard martensitic/ bainitic second phase. The concept of representative volume element (RVE) is c...

By Emina Vardo, Aida Imamović, Jessica Gola

This work aims at the development of low-carbon steel SAE 1006 through the microalloying addition of boron. Boron as alloying element is added in small amount, but it has significant effect on changes of properties of this kind of steel. The research is based on mechanical and microstructural testing of final product (wire) from the aspect of the i...

By Aida Imamović, Alma Puljić, Omer Kablar

The chemical composition of casting is an important factor affecting the shape of graphite and the mechanical properties and microstructure of the metal base. Different elements have different influence to casting properties. All elements that affect the microstructure development during casting solidification have significant influence on mechanic...

By Aida Imamović, Hasan Avdušinović, Anida Henjaković