The effect of sodium and strontium on modification of eutectic silicon

Modification of eutectic (αAl+βSi) is usually performed during treatment of Al-Si based alloys in order to obtain higher mechanical properties. Chemical modification is usually performed using modifying elements such as Na and Sr. The research was performed in order to estimate the efficiency of Na and Sr additions in eutectic AlSi12 alloy using chemical analysis, simple thermal analysis (STA) and metallographic analysis. The metallographic analysis revealed fully modified (αAl+βSi) eutectic microstructure in alloy treated with Na. The Sr additions widened solidification interval and, lowered the eutectic area temperatures as indicated by STA

INTERMETALLIC BONDING BETWEEN A RING CARRIER AND AN ALUMINUM PISTON ALLOY

Abstract This paper presents an analysis of the intermetallic bond between a ring carrier and an aluminum piston alloy. An optical microscope combined with the SEM / EDS analysis has been used to metallographically analyze the quality of the intermetallic bonding layer. The obtained results show that can be established intermetallic bond between two materials of different qualities

Influence of copper content on microstructure development of AlSi9Cu3 alloy

Microstructure development and possible interaction of present elements have been determined in charge material of EN AB AlSi9Cu3 quality. Literature review enables prediction of solidification sequence. Modelling of equilibrium phase diagram for examined chemical composition has been performed, which enables determination of equilibrium solidification sequence. Microstructural investigation indicated distribution and morphology of particular phase. Metallographic analysis tools enable exact determination of microstructural constituents: matrix α Al, eutectic αAl+βSi, iron base intermetallic phase - Al5FeSi, Alx(Fe,Mn)yCuuSiw and/or Alx(Fe,Mn)yMgzCuuSiw and copper base phases in ternary eutectic morphology Al-Al2Cu-Si and in complex intermetallic ramified morphology Alx(Fe,Mn)yMgzSiuCuw. Microstructure development examination reveals potential differences due to copper content which is prerequisitefor high values of final mechanical, physical and technological properties of cast products

Influence of cooling rates on temperatures phase transitions and on microstructure of aluminium alloy EN AW-5083

The casting of different forms and dimensions of aluminium alloy EN WA-5083 test samples and the usage of different types of mould materials resulted in achieving different cooling rates of samples. The methods used were simple thermal analysis, using casting into a measuring cell made by the Croning process and using casting into a cone-shaped measuring cell, as well as simultaneous thermal analysis using the method of differential scanning calorimetry. Significant temperature phase transitions and times of solidification were determined, and the dependence model of the solidification time on the sample cooling rate was obtained. Determining the mean number of grains per unit area on samples after having performed the simple thermal analysis and differential scanning calorimetry makes it possible to develop a dependence model of the mean number of grains per unit area on the cooling rate. These models are the basis for carrying out numerical simulations of solidification and microstructure development in the cone-shaped measuring cell, and the comparison of the distribution of the mean number of grains per unit area obtained by simulation with the one obtained experimentally. The obtained results represent a part of the preliminary tests of the microstructure development of industrially cast ingots of EN AW-5083 alloy depending on the local ingot cooling rate.Beim Gießen verschiedener Versuchsmuster mit unterschiedlichen Formen und Grßen der Aluminiumlegierung EN WA-5083 und Verwenden verschiedener Formstofftypen, wurden unterschiedliche Abkhlgeschwindigkeiten festgestellt. Dabei wurde die Methode der einfachen Thermalanalyse angewendet, die beim Gießen in eine Messzelle einmal mit dem Croning-Verfahren hergestellt wurde und einmal in eine kegelfrmige Messzelle gegossen wurde, samt gleichzeitiger Thermalanalyse mit der Methode der differenziertenWrmemessung. Dabei wurden die Temperaturphasen bergnge und Zeiten bis zur Erstarrung ermittelt sowie das Zeit-Modell in Abh ngigkeit der Abkhlgeschwindigkeit bis zur Erstarrung der Versuchsprobe ermittelt. Durch die Bestimmung des Mittelwertes der Anzahl der Krner pro Flche auf der Versuchsprobe nach der durchgefhrten einfachen Thermalanalyse und der Methode der differenziertenWrmemessung, kann ein Abhngigkeitsmodell des Mittelwertes der Anzahl der Krner pro Flche ber die Abk hlgeschwindigkeit erstellt werden. Diese Modelle sind die Basis, um die numerische Simulation des Festwerdens und die Mikrostruktur-Entwicklung in der kegelfrmigen messenden Zelle, samt der Simulation des Vergleichs der Verbreitung des Mittelwertes der Anzahl von Krnern pro Fl- che zu erlangen. Die erhaltenen Ergebnisse reprsentieren einen Teil der Forschung der Mikrostruktur- Entwicklung beim industriellen Gießen von Blcken der Legierung EN AW-5083 in Abh ngigkeit der lokalen Abkhlgeschwindigkeit der Blcke

The effect of sodium and strontium on modification of eutectic silicon

Modification of eutectic (αAl+βSi) is usually performed during treatment of Al-Si based alloys in order to obtain higher mechanical properties. Chemical modification is usually performed using modifying elements such as Na and Sr. The research was performed in order to estimate the efficiency of Na and Sr additions in eutectic AlSi12 alloy using chemical analysis, simple thermal analysis (STA) and metallographic analysis. The metallographic analysis revealed fully modified (αAl+βSi) eutectic microstructure in alloy treated with Na. The Sr additions widened solidification interval and, lowered the eutectic area temperatures as indicated by STA

Identification of Phases Formed by Cu and Ni in Al?Si Piston Alloys

This paper presents the results of identifying and analyzing the phases present in the microstructure of 4 aluminum piston alloys with different chemical composition. Optical microscopy and scanning electron microscopy were used to study the microstructure of the samples and EDS analysis was used to identify thecomposition of the phases. The phase stoichiometry was identified by comparing the results of EDS analysis with the results reported in the studied literature. The results show that different intermetallic phases can appear depending on the chemical composition of the microstructure of aluminum piston alloys

CANCER PATIENTS FOLLOW-UP – CROATIAN SOCIETY OF MEDICAL ONCOLOGY CLINICAL GUIDELINES Part III: neuroendocrine neoplasms, hepatocellular carcinoma, pancreatic cancer, cancer of the bile ducts

Liječenje onkoloških bolesnika mora se temeljiti na multidisciplinarnom pristupu, a provodi se u specijaliziranim onkološkim centrima. Nakon završetka specifičnog onkološkog liječenja daljnje praćenje uglavnom provode onkolozi, ali je uloga liječnika primarne zdravstvene zaštite (PZZ) sve važnija i potrebno ju je jasno definirati. Trenutačno se većina preporuka za praćenje ne temelji na prospektivnim studijama, već se zasniva na stručnim mišljenjima pojedinih onkoloških centara ili specijalista. Hrvatsko društvo za internističku onkologiju (HDIO) ovim preporukama želi standardizirati i racionalizirati dijagnostičke postupke u praćenju onkoloških bolesnika, nakon završetka primarnog liječenja, u bolesnika s neuroendokrinim neoplazmama, hepatocelularnim karcinomom, rakom gušterače i rakom žučnih vodova.The treatment of oncological patients must be based upon multidisciplinary approach, and takes place in specialized oncological centers. By the end of a specific oncological treatment further follow-up is being managed mostly by the oncologists, but the role of the general practitioners becomes more important every day and therefore should be precisely defined. Nowadays, most of the existing follow-up guidelines are not based on prospective studies, but on the experts opinion of individual oncological centers or specialists. The aim of the Croatian Society of Medical Oncology (CSMO) with these recommendations is to standardize and rationalize the diagnostic procedures algorithm in the follow-up of oncological patients after primary treatment, in patients with neuroendocrine neoplasms, hepatocellular carcinoma, pancreatic cancer and cancer of the bile ducts

Praćenje onkoloških bolesnika – kliničke preporuke Hrvatskog društva za internističku onkologiju HLZ-a III. dio: neuroendokrine neoplazme, hepatocelularni karcinom, rak gušterače, rak žučnih vodova [Cancer patients follow-up – Croatian society of medical oncology clinical guidelines Part III: neuroendocrine neoplasms, hepatocellular carcinoma, pancreatic cancer, cancer of the bile ducts]

The treatment of oncological patients must be based upon multidisciplinary approach, and takes place in specialized oncological centers. By the end of a specific oncological treatment further follow-up is being managed mostly by the oncologists, but the role of the general practitioners becomes more important every day and therefore should be precisely defined. Nowadays, most of the existing follow-up guidelines are not based on prospective studies, but on the experts opinion of individual oncological centers or specialists. The aim of the Croatian Society of Medical Oncology (CSMO) with these recommendations is to standardize and rationalize the diagnostic procedures algorithm in the follow-up of oncological patients after primary treatment, in patients with neuroendocrine neoplasms, hepatocellular carcinoma, pancreatic cancer and cancer of the bile ducts

CANCER PATIENTS FOLLOW-UP – CROATIAN SOCIETY OF MEDICAL ONCOLOGY CLINICAL GUIDELINES Part III: neuroendocrine neoplasms, hepatocellular carcinoma, pancreatic cancer, cancer of the bile ducts

Liječenje onkoloških bolesnika mora se temeljiti na multidisciplinarnom pristupu, a provodi se u specijaliziranim onkološkim centrima. Nakon završetka specifičnog onkološkog liječenja daljnje praćenje uglavnom provode onkolozi, ali je uloga liječnika primarne zdravstvene zaštite (PZZ) sve važnija i potrebno ju je jasno definirati. Trenutačno se većina preporuka za praćenje ne temelji na prospektivnim studijama, već se zasniva na stručnim mišljenjima pojedinih onkoloških centara ili specijalista. Hrvatsko društvo za internističku onkologiju (HDIO) ovim preporukama želi standardizirati i racionalizirati dijagnostičke postupke u praćenju onkoloških bolesnika, nakon završetka primarnog liječenja, u bolesnika s neuroendokrinim neoplazmama, hepatocelularnim karcinomom, rakom gušterače i rakom žučnih vodova.The treatment of oncological patients must be based upon multidisciplinary approach, and takes place in specialized oncological centers. By the end of a specific oncological treatment further follow-up is being managed mostly by the oncologists, but the role of the general practitioners becomes more important every day and therefore should be precisely defined. Nowadays, most of the existing follow-up guidelines are not based on prospective studies, but on the experts opinion of individual oncological centers or specialists. The aim of the Croatian Society of Medical Oncology (CSMO) with these recommendations is to standardize and rationalize the diagnostic procedures algorithm in the follow-up of oncological patients after primary treatment, in patients with neuroendocrine neoplasms, hepatocellular carcinoma, pancreatic cancer and cancer of the bile ducts

Utjecaj temperature žarenja na mikrostrukturu i tvrdoću AlSi10Mg dijelovaproizvedenih SLM aditivnim postupkom

SLM proizvodnja Co-Cr dentalnih legura je relativno novo područje inženjerstva materijala. Utjecaj pojedinih parametara SLM postupka na strukturu i svojstva konsolidiranih Co-Cr dentalnih legura i njihova interakcija predstavlja važno područje za istraživanje. Preliminarna istraživanja koja su provedena na proporcionalnim uzorcima izrađenima od istog komercijalnog praha Co-Cr legure SLM postupkom na strojevima različitih proizvođača koristeći preporučene parametre postupka pokazala su velike razlike u mikrostrukturi dobivenih uzoraka te značajna rasipanja vrijednosti mehaničkih svojstava konsolidiranog materijala (vlačna i savojna čvrstoća, istezanje i žilavost). Rasipanja rezultata nisu uočena samo između uzoraka izrađenih na različitim strojevima, već i između uzoraka različitih šarži na istom stroju. Dobiveni rezultati preliminarnih istraživanja pokazuju da u samoj proizvodnji Co-Cr legura SLM postupkom dolazi do utjecaja pojedinih parametara koji značajno utječu na kvalitetu dobivenog proizvoda. Ta povezanost glavnih tehnoloških parametara SLM proizvodnje sa strukturom i svojstvima proizvoda i njihova interakcija je velikim dijelom nepoznato područje i predstavlja veliki znanstveno istraživački potencijal, gdje rezultati istraživanja mogu doprinijeti optimizaciji strukture i svojstava dentalnih Co-Cr legura. U ovom istraživanju planira se napraviti ispitivanje utjecaja pojedinih parametara DSLM postupka, i to snage lasera te brzine taljenja na mehanička svojstva (vlačnu, tlačnu i savojnu čvrstoću) Co-Cr legure za dentalnu namjenu. Također će se napraviti i analiza mikrostrukture kojom će se utvrditi utjecaj pojedinih parametara na ispitivana mehanička svojstva.SLM production of Co-Cr dental alloys is a relatively new field of materials engineering. The influence of individual parameters of the SLM procedure on the structure and properties of consolidated Co-Cr dental alloys and their interaction is an important area for research. Preliminary studies conducted on proportional samples made of the same commercial powder Co-Cr alloy SLM process on machines of different manufacturers using the recommended process parameters showed large differences in the microstructure of the obtained samples and significant differences in mechanical properties of consolidated material (tensile and flexural strength, elongation and toughness). Scattering of the results was observed not only between samples made on different machines, but also between samples of different batches on the same machine. The obtained results of preliminary research show that in the production of Co-Cr alloys by SLM process there is an influence of certain parameters that significantly affect the quality of the obtained product. This connection of the main technological parameters of SLM production with the structure and properties of products and their interaction is largely an unknown area and represents great scientific research potential, where research results can contribute to optimizing the structure and properties of dental Co-Cr alloys. In this research, it is planned to examine the influence of certain parameters of the DSLM procedure, namely laser power and melting rate on the mechanical properties (tensile, compressive and flexural strength) of Co-Cr alloy for dental purposes. A microstructure analysis will also be performed to determine the influence of individual parameters on the examined mechanical properties