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Abrasive wear of BA1055 bronze with additives of Si, Cr, Mo and/or W  [PDF]
B. P. Pisarek
Archives of Foundry Engineering , 2008,
Abstract: Aluminium bronzes belong to the high-grade constructional materials applied on the put under strongly load pieces of machines, aboutgood sliding, resistant properties on corrosion both in the cast state how and after the thermal processing. It moves to them Cr and Si in the aim of the improvement of their usable proprieties. The additions Mo and/or W were not applied so far. It was worked out therefore the new kind of bronzes casting including these elements. Make additions to the Cu-Al-Fe-Ni bronze of Si, Cr, Mo and/or W in the rise of these properties makes possible. The investigations of the surface distribution of the concentration of elements in the microstructure of the studied bronze on X-ray microanalyzer were conducted. It results from conducted investigations, that in the aluminium bronze BA1055 after makes additions Si, Cr, Mo and/or W the phases of the type κFe, κNi crystallize, probably as complex silicides. Elements such as: Fe and Si dissolve first of all in phases κ, in smaller stage in the matrix of the bronze; Mn, Ni and W they dissolve in matrix and phases κ. It dissolves Cr and Mo in the larger stage in phases κ than in the matrix. The sizes of the abrasive wear were compared in the state cast multicomponentnew casting Cu-Al-Fe-Ni bronzes with the additives Cr, Mo or W with the wear of the bronze CuAl10Fe5Ni5Si. The investigations of thewear were conducted on the standard device. It results from conducted investigations, that make additions to bronze BA1055 of the additives of Si, Cr, Mo, and/or W it influences the rise of the hardness (HB) of the bronze in the cast state, in the result of the enlarged quantity separates of hard phases κ, and in the consequence the decrease of the abrasive wear. The addition of molybdenum made possible obtainment of the microhardness of the phase α and γ 2 on the comparable level. From the microstructure of the bronze CuAl10Fe5Ni5MoSi is characterizes the smallest abrasive wear among studied bronzes. More far works over new multicomponent aluminium bronzes will be guided in the direction of the identification of the changes of mechanical properties of studied bronzes under the influence of the thermal processing.
Effect of two-stage isothermal annealing on microstructure CuAl10Fe5Ni5 bronze with additions of Si, Cr, Mo, W and C  [PDF]
B. P. Pisarek
Archives of Foundry Engineering , 2011,
Abstract: The aim of this study was to investigate the effect of a two-step isothermal annealing respectively at 1000 C for 30 min, then at the range of 900÷450 C increments 50 C on the microstructure CuAl10 Ni5Fe5 bronze with additions of Si, Cr, Mo, W and C, cast into sand moulds. The study concerned the newly developed species, bronze, aluminium-iron-nickel with additions of Si, Cr, Mo, W and C. In order to determine the time and temperature for the characteristic of phase transitions that occur during heat treatment of the test method was used thermal and derivation analysis (TDA). The study was conducted on cylindrical test castings cast in the mould of moulding sand. It was affirmed that one the method TDA can appoint characteristic for phase transformations points about co-ordinates: τ (s), t ( C), and to plot out curves TTT for the studied bronze with their use. It was also found that there is a fiveisothermalannealingtemperatureranges significantly altering the microstructure of examined bronze.
The crystallisation of the aluminium bronze with additions of Si, Cr, Mo and/or W
B.P. Pisarek
Archives of Materials Science and Engineering , 2007,
Abstract: Purpose: The aim of this paper is description of the process of the crystallization of new aluminium bronzes with the complex silicides of the iron.Design/methodology/approach: Additions Cr, W, Mo and Si were introduced to create in the microstructure of the aluminium bronze of the complex silicides of the iron about high mechanical and physical proprieties to the bronze BA1044. The process of formation the microstructure of the bronze with use of the method of the thermal and derivative analysis (TDA) was analysed. The examinations under the microscope and X-ray microanalysis of the surface distribution of elements were conducted.Findings: From carried research results, that in the aluminium bronze BA1044 after addition Si, Cr, Mo and/or W the phase κFe, κNi crystallize as the complex silicides of the iron. Elements such as: Fe and Si dissolve first of all in silicides in the smaller stage in the matrix of the bronze, Mn and Ni they dissolve in matrix and silicides, Cr dissolves in the larger stage in silicides than in the matrix, W and Mo dissolve in silicides however they crystallize as nanocrystals in the metal matrix and create with her composite.Research limitations/implications: Results of investigations of aluminium bronze BA1044 and alloys after adding to him about 1% Si were introduced in the article and suitably: 1.22 % Cr; 0.82 % Mo; 0.020 % W; 0.60 % Cr, 0.17 % Mo and 0.017 % W.Originality/value: The original results of the investigations of the crystallization of the new bronzes (innovative materials and casting technologies) for which the process of arising microstructure the method TDA was not analysed so far were introduced in the article. The article possesses cognitive values not only essential for researcher but and practician-melters.
Effect of additions of Cr, Mo, W and/or Si on the technological properties of aluminum-iron-nickel bronze  [PDF]
B. P. Pisarek
Archives of Foundry Engineering , 2011,
Abstract: The aim of this study was to investigate the effect of additives of Cr, Mo, W and / or Si CuAl10Fe5Ni5 bronze, cast into sand moulds, the bronze technological properties such as: porosity, volumetric shrinkage Sv, linear shrinkage s and prone hot to cracking. The study relate to the newly developed grades aluminum-iron-nickel bronze, with additions of Cr, Mo, W and/or Si. In order to determine the technological properties of the test castings were made in the form of moulding sand, which made the mould cavities designed patterns. To evaluate the porosity and volumetric shrinkage was used for digital image analysis method. Volumetric shrinkage was determined using developed, the new method, the surface shrinkage Svp designation, and then converting it to the volumetric shrinkage, using prepared relation Sv=f(Djs)*Svp. It was found that made the bronze alloy additions to reduce the size of pores surface area of gas and shrinkage in the test bronze. The probability of microporosity with an area of 0.002560÷0.120647 mm2 can be described by gamma distribution. Changing the chemical composition of the grades tested bronze strongly alter the first volumetric shrinkage Sv, and less to change the linear shrinkage s. The increase in gas porosity and shrink in bronze reduces the volumetric shrinkage and linear. The addition of Cr, Mo, W and/or Si to the bronze CuAl10Fe5Ni5 does not change its prone to hot cracking.
Effect of Annealing Time for Quenching CuAl7Fe5Ni5W2Si2 Bronze on the Microstructure and Mechanical Properties  [PDF]
B. P. Pisarek
Archives of Foundry Engineering , 2012,
Abstract: This paper presents the influence of annealing time 30, 60 and 120 min at 1000°C for quenching CuAl7Fe5Ni5W2Si2 bronze in 10% water solution of NaCl, on the microstructure and mechanical properties. The presented results concern the species newly developed aluminum-iron-nickel bronze, with additions W and Si.In order to determine changes in the microstructure of the hardened bronze metallographic studies were performed on cylindrical samples of diameter 10 mm, on the metallographic microscope with digital image analysis, X-ray phase analysis, EDX point with the digital recording on the computer. Specified percentage of the microstructure of martensite and bainite, participation of proeutectoid α phase in the microstructure, grain size of former β phase, the amount of dissolved κ phase.It was found that in the microstructure of bronze in the cast state, there are a number of intermetallic phases of κ type. At interphase boundaries of primary intermetallic faceted precipitates, especially rich in tungsten (IM_W), nucleate and grow dendritic primary intermetallic κI phases, with chemical composition similar to the type of Fe3Si iron silicide.Dissolved, during the heating, in the β phase are all the intermediate phase included in the microstructure, with the exception of primary intermetallic phases of tungsten and κI. Prolongation of the isothermal annealing causes coagulation and coalescence of primary phases. In microstructure of the bronze after quenching obtained the α phase precipitation on the grain boundary of secondary β phase, coarse bainite and martensite, for all annealing times. With the change of annealing time are changed the relative proportions of individual phases or their systems, in the microstructure. In the microstructure of bronze, hold at temperature of 1000°C for 60 min, after quenching martensitic microstructure was obtained with the primary phases, and the least amount of bainite.
Effect of Combined Additions of Mo-B on Transformation and Microstructure of Ultra High-strength Pipeline Steels

WEI Wei,

金属学报 , 2007,
Abstract: The transformation characteristic, microstructure and micro-hardness for ultra high-strength pipeline steels with different content of Mo and B as well as different Mo/B ratio were investigated in this paper. Combined additions of Mo and B were found to more effectively increase the hardenability of the steel than the individual effectiveness of these two elements, which increase the volume fraction of bainite in microstructure and enhance the hardness of the steel. The experimental results showed that there should be an optimum Mo/B ratio to achieve the optimum microstructure and mechanical properties of the steel. The mechanism for the combined Mo-B effect on ultra high-strength pipeline steels was also discussed.
The influence of heat treatments on cavitation erosion resistance of BA1055 alloy
R. Jasionowski,W. Przetakiewicz,W. Przetakiewicz,S. Czorna
Archives of Foundry Engineering , 2009,
Abstract: The cavitation erosion is a process of material deterioration as a result of materialization, increase and decrease of the cavitation bubbles in different types of liquid. The cavitation erosion materials are used to prevent the devastating effect of imploding bubbles. The aluminium bronze BA1055 is the most commonly used material among the cooper alloys used on the parts of machines exposed to cavitation erosion phenomenon. The following article brings up the study of the effects of bronze BA1055 heat treatment for its cavitation erosion resistance performed on a flux-impact measuring device. The conducted studies confirmed the extension of the incubation process of BA1055 alloy after the hardening in relation to the moulded alloy. It has resulted in the increase of the resistance to cavitation erosion.
Crystallisation and microstructure of low-silicon silumins with alloy additions  [PDF]
S. Pietrowski
Archives of Foundry Engineering , 2011,
Abstract: The paper presents the results of the analysis of crystallisation and microstructure of non-alloy silumins that contain: 2,0÷6,0% of Si and alloy additions, approximately: 4,0% Ni, 4,0% of Cu and 0,5% of Mg, the knowledge of which is still very little. It has been proven that in non-alloy silumins, the increase of silicone concentration causes extending of crystallisation time of the eutectic mixture α+and refinement of α phase dendrites. It also causes the increase of the temperature of crystallisation of the eutectic mixture α+ . Alloy additions: Ni, Cu and Mg decrease by approximately 30 C the liquidus and solidus temperatures of silumins and extend the time of their crystallisation by around 100 sec. in comparison with non-alloy silumins. It is caused by crystallisation of additional phases Al3NiCu, Mg2Si and Al2Cu. Nickel, copper and magnesium refine the microstructure of castings.

WANG Jihui,JIANG Xiaoxia,LI Shizhuo,

金属学报 , 1996,
Abstract: The effects of boron on the microstructure,mechanical properties,corrosion and corrosive wear resistance of aluminium bronzes were investigated systematically.The results show that the addition of boron can fine the grain size,increase the strength and hardness of aluminium bronze without greatly affecting its plasticity,the selective corrosion and corrosive wear resistance were also improved.The mechanism of boron in aluminium bronze was discussed.
Influence of Al and Ti Additions on Microstructure and Mechanical Properties of Leaded Brass Alloys  [PDF]
Rajab Mohammed Hussein,Osama Ibrahim Abd
Indian Journal of Materials Science , 2014, DOI: 10.1155/2014/909506
Abstract: Brass has an attractive combination of properties, namely, good corrosion resistance, good wear properties, and high thermal and electrical conductivity. In this study, influence of selected alloy additions (Al and Ti) on performance of leaded brass alloys (CuZn39pb3) was investigated. The observation of microstructures, compression tests, and hardness tests were performed. The results of metallographic and mechanical tests indicate some influence of small amount additives of Al and Ti. Optical emission spectrometer (OES), light optical microscope (LOM), micro-Vickers hardness tester, and compression testing machine were used in this investigation. Consequently, Al had a significant effect on microstructure and mechanical properties of CuZn39Pb3 alloy. A larger compression strength at 0.31% wt of Al was obtained, as compared with the other alloys. Adding of Al and Ti led to the modification of the microstructure; thus, the compression strength was increased. 1. Introduction Cu-Zn alloy is widely used as an industrial material because of its excellent characteristics such as high corrosion resistance, nonmagnetism, and good machinability. In particular, machinable brass is obtained by adding lead [1]. High copper contents (larger than 60%) are needed to produce products by cold working in order to have a good enough formability. When a good machining behaviour is required, lead is added (until 3%). The benefits conferred by the presence of lead have been appreciated for many years to facilitate chip fracture, reduce cutting forces, increase the machining rate and productivity, reduce tool wear, and enhance surface finish [2]. Major improvements in performance occur when the structure changes from all-beta to alpha + beta [duplex] and from duplex to all-alpha phase. Alloys containing less than 15% Zn are rarely dezincified. Some alloying additions have a large effect on the structure of brass, by altering the proportion of alpha, beta, or gamma phase present [3]. Alloying elements are added as solid solution strengtheners like Al, Mn, and Fe; these additives lead to the increase of the area fraction of hard -phase. However, when these strengtheners are added with large amounts, the coarser and brittle intermetallic compounds form the matrix, and the drastic decrease occurs. Hence, brass alloys require to be strengthened by small amounts of additives to decrease the content of intermetallic compounds (IMCs) and disperse fine in the matrix [4]. Grain refiners are materials added to alloys to aid in nucleation and lead to the production of fine and uniform
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