Refining processes in the copper casting technology

The paper presents the analysis of technology of copper and alloyed copper destined for power engineering casts. The casts quality was assessed based on microstructure, chemical content analysis and strength properties tests. Characteristic deoxidising (Logas, Cup) and modifying (ODM2, Kupmod2) formulas were used for the copper where high electrical conductivity was required. Chosen examples of alloyed copper with varied Cr and Zr content were studied, and the optimal heat treatment parameters were tested for a chosen chromium copper content, based on the criterion of hardness and electrical conductivity tests. Searching for materials with high wear resistance, the influence of variable silicone content on the properties of CuNiSi alloy was researched

Influence of refining treatments on the properties of Al-Si alloys

The article focused on researching the influence of Ti, B, Sr and Na as a modifying treatment elements for Al-Si alloys. The influence of alloying additives such as Cu and Cr was studied. Tensile strength Rm, elongation A5 and HB hardness was analysed, as well as the influence of the above-mentioned elements on the microstructure and solidification of alloys containing a varied content of Si, within the 7 ÷ 16 % range. The influence of heat treatment on the alloy properties was also researched

Copper alloys in investment casting technology

This paper presents research results in the field of casting technology of copper and copper alloys using the investment casting technology, both from historical as well as modern technology perspective. The analysis of exemplary elements of the old casting moulds is included, as well as the Bronze Age casts. The chemical content of various copper alloys was determined and the application of lost wax method was confirmed in the Bronze Age workshop. At present, investment casting method is used for manufacturing high-quality casts, especially products for power engineering that is why it demands respecting very rigorous technological requirements. The casts were characterised based on microstructure research, chemical composition and conductivity in relation to oxygen content

Effect of Alloying Additives and Casting Parameters on the Microstructure and Mechanical Properties of Silicon Bronzes

The studied silicon bronze (CuSi3Zn3Mn1) is characterised by good strength and corrosion resistance due to the alloying elements that are present in it (Si, Zn, Mn, Fe). This study analysed the casting process in green sand moulding, gravity die casting, and centrifugal casting with a horizontal axis of rotation. The influences of Ni and Zr alloying additives as well as the casting technology that was used were evaluated on the alloy’s microstructure and mechanical properties. The results of the conducted research are presented in the form of the influence of the technology (GS, GZ, GM) and the content of the introduced alloy additives on the mechanical parameters (UTS, A10, and Proof Stress, BHN). The analysis of the tests that were carried out made it possible to determine which of the studied casting technologies had the best mechanical properties. Microstructure of metal poured into metal mould was finer than that which was cast into moulding compound. Mechanical properties of castings made in moulding compound were lower than those that were cast into metal moulds. Increased nickel content affected the BHN parameter

Effect of Microstructure of Fe-C-V Alloys on Selected Functional Properties

The cast alloys crystallizing in Fe-C-V system are classified as white cast iron, because all the carbon is bound in vanadium carbides. High vanadium cast iron has a very high abrasion resistance due to hard VC vanadium carbides. However, as opposed to ordinary white cast iron, this material can be treated using conventional machining tools. This article contains the results of the group of Fe-C-V alloys of various microstructure which are been tested metallographic, mechanical using an INSTRON machine and machinability with the method of drilling. The study shows that controlling the proper chemical composition can influence on the type and shape of the crystallized matrix and vanadium carbides. This makes it possible to obtain a high-vanadium cast iron with very high wear resistance while maintaining a good workability

Researching the Influence of Chemical Composition and Technological Parameters on the Quality of Copper Alloys

The work presents the results of process efficiency of refining liquid copper with special refining agents and the analysis results of the influence of alloying components on the structure and properties of the chosen alloys. The research undertaken aimed at evaluation of the influence of alloying additives, such as aluminium, silicon and also cobalt in the chosen Cu-Zn alloys. The microstructures were researched with the help of light and scanning microscopy together with X-ray microanalysis to determine significant changes of mechanical properties

Effect of Microstructure of Fe-C-V Alloys on Selected Functional Properties

The cast alloys crystallizing in Fe-C-V system are classified as white cast iron, because all the carbon is bound in vanadium carbides. High vanadium cast iron has a very high abrasion resistance due to hard VC vanadium carbides. However, as opposed to ordinary white cast iron, this material can be treated using conventional machining tools. This article contains the results of the group of Fe-C-V alloys of various microstructure which are been tested metallographic, mechanical using an INSTRON machine and machinability with the method of drilling. The study shows that controlling the proper chemical composition can influence on the type and shape of the crystallized matrix and vanadium carbides. This makes it possible to obtain a high-vanadium cast iron with very high wear resistance while maintaining a good workability

Lead-Free Casting Brasses. Investigations of the Corrosion Resistance and Shaping of Microstructure and Properties

The ecological factor is very important in shaping properties of alloys. It leads to a limitation or elimination, from the surroundings, of harmful elements from the heavy metals group. The so-called eco-brasses group comprises common lead-free brasses containing 10 to 40% of zinc and arsenic brasses of a high dezincification resistance. Among standardized alloys, CW511L alloy ( acc. to EN standard) or MS-60 alloy (acc. to DIN) can be mentioned. Investigations were performed on two different kinds of metal charges: ingots cast by gravity and the ones obtained in the semi-continuous casting technology with using crystallizers. The casting quality was analysed on the basis of the microstructure images and mechanical properties. The investigations also concerned increasing the corrosion resistance of lead-free alloys. This resistance was determined by the dezincification tendency of alloys after the introduction of alloying additions, i.e. aluminium, arsenic and tin. The investigations focused on the fact that not only alloying additions but also the production methods of charge materials are essential for the quality of produced castings. The introduced additions of aluminium and tin in amounts: 0÷1.2 wt% decreased the dezincification tendency, while arsenic, already in the amount of 0.033 wt%, significantly stopped corrosion, limiting the dezincification process of lead-free CuZn37 brass. At higher arsenic contents, corrosion occurs only within the thin surface layer of the casting (20 μ)

Analiza struktury i właściwości mosiądzów bezołowiowych

The analysis of brasses regarding their microstructure, mechanical properties and ecological characteristics has been presented. The influence of characteristic alloying elements contained in the brasses and the possibilities of replacing them with other elements have been assessed. The paper contains the results of studies on the influence of chosen additional elements shaping the structure and properties of unleaded alloys based on Cu-Zn system as the matrix. The research aimed at determining the mechanism and the intensity of influence of such additives as tellurium and bismuth. The microstructures were investigated with the help of light microscopy and scanning electron microscopy with X-ray microanalysis (SEM-EDS) for determining significant changes of the properties.Przedstawiono analizę mosiądzów w zakresie mikrostruktury, właściwości wytrzymałościowych oraz charakterystyki ekologicznej. Poddano ocenie wpływ charakterystycznych pierwiastków stopowych zawartych w mosiądzach i możliwości zastąpienia ich innymi. W pracy ujęto wyniki badań wpływu wybranych dodatkowych pierwiastków kształtujących strukturę i właściwości bezołowiowych stopów na osnowie układu Cu-Zn. Podjęte badania miały na celu określenie mechanizmu i intensywności oddziaływania dodatków takich jak: tellur i bizmut. Przeprowadzono badania mikrostruktur z wykorzystaniem mikroskopii świetlnej oraz mikroskopii skaningowej z mikroanalizą rentgenowską SEM-EDS, dla określenia istotnych zmian właściwości