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The influence of wall thickness on the microstructure of bronze BA1055 with the additions 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, about good 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. Additions Mo and/or W were not applied so far in the larger concentration, these elements were introduced to the melts of the copper as the components of modifiers. 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 influence of the wall thickness of the cast on size of crystallites were conducted: the primary phase β and intermetallic phase κ and the width separates of the secondary phase α precipitate at phase boundary. It results from conducted investigations, that in the aluminium bronze BA1055 after simultaneous makes additions Si, Cr, Mo and in the primary phase β it undergoes considerable reducing size. The addition W reduce size of the grain phase β in the thin walls of the cast 3-6 mm, and addition Cr in the range of the thickness of the wall of the cast 3-6 mm it favors to reducing size the phase β, in walls 12-25 mm the growth causes it. The addition Mo does not influence the change of the size of the grain of the β phase significantly. The make addition singly or simultaneously of the Cr, Mo and W to the bronze CuAl10Fe5Ni5Si it influences the decrease of the quantity separates of the phase α on the interface boundary and of width it separates independently from the thickness of the wall of the cast. The simultaneous make addition of the Si, Cr, Mo and W it enlarges the surface of the phase κFe, κMo. The make addition to the bronze CuAl10Fe5Ni5Si of the Cr, Mo or W the quantity of crystallizing hard phase κ enlarges and the hardness HB of the bronze raises. The make addition singly the Mo or W, if also simultaneous with the addition Cr reduces their make addition it sensibility on the change of the thickness of the wall of the cast (3-25 mm) guaranteeing the possibly small fall the hardness the bronze about 22-28 HB. 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.
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 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.
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.
Phases created during diffusion bonding of aluminium and aluminium bronze chips  [PDF]
J. Gronostajski,W. Chmura,Z. Gronostajski
Journal of Achievements in Materials and Manufacturing Engineering , 2006,
Abstract: Purpose: The main aim of the paper is to apply the new sintering criterion to determinate the sintering conditions and to investigate the phases created during bonding aluminium and aluminium bronze and their effect on the composites properties.Design/methodology/approach: An original concept of producing a composite, consisting in the mixing and bonding of aluminium chips with aluminium bronze chips through press moulding and extrusion, has been developed. As a result of the reciprocal diffusion of copper and aluminium during extrusion and heat treatment applied just after extrusion a creation of hard phases leading to an increase of wear resistant takes place.Findings: Heat treatment applied after extrusion improves tribological properties and hardness of composites by increase of diffusion bonding and creation of new phases. To obtain the bonding of particles separated by a layer of oxide and a highly compacted product, two conditions must be fulfilled: thin aluminium oxide and large shear plastic deformationPractical implications: The proposed new sintering criterion allows to determined condition of sintering and deformation in order to obtain good product. This criterion can be applied in FEM.Originality/value: Diffusion bonding process of aluminium and aluminium bronze chips leads to creation of phases typical for Cu-Al alloys. The bonding takes place during extrusion of cold compacted mixture of aluminium and aluminium bronze chips and during heat treatment applied after extrusion. In this way, without participation of metallurgical processes good bearing materials can be manufactured.
Corrosion Characteristics of As-Cast Aluminium Bronze Alloy in Selected Aggressive Media  [PDF]
Bukola Joseph Babalola, Michael Oluwatosin Bodunrin, Joseph Olatunde Borode, Kenneth Kanayo Alaneme
Journal of Minerals and Materials Characterization and Engineering (JMMCE) , 2013, DOI: 10.4236/jmmce.2013.15038
Abstract: This research work investigated the corrosion characteristics of aluminium bronze alloy in four selected aggressive media which are H2SO4, HCl, NaOH, and NaCl. Aluminium bronze alloy was produced locally via sand casting method. Copper coils and aluminium materials which constitute waste to the environment were used in producing the alloy. Test specimens were produced from the as cast alloy and immersed in H2SO4, HCl, NaOH, and NaCl environment. The concentrations of the environment were varied as 0.1 M, 0.3 M and 0.5 M. The aluminium bronze produced from sand casting has mechanical properties that are closer to the standards proposed by CDA [1]. The corrosion rate was determined by weight loss method at an interval of 3 days. It was observed that the corrosion behaviour exhibited by aluminium bronze in acidic media followed similar trends in 0.1 M, 0.3 M and 0.5 M respectively. However, the corrosion rates increases with increase in the concentration of H2SO4 and NaCl media, but the attack was more aggressive in HCl medium. The aluminium bronze samples in NaOH and H2SO4 media show gradual decolouration from its as-cast yellow golden colour to brown and dark colour respectively. NaCl environment shows high resistance to corrosion and slight decolouration effect even at increased concentration.
MICROSTRUCTURE AND PROPERTIES OF BORON-MODIFIED ALUMINIUM BRONZE
加硼铝青铜的组织和性能

WANG Jihui,JIANG Xiaoxia,LI Shizhuo,
王吉会
,姜晓霞,李诗卓

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.
Mechanical Properties and Microstructures of Locally Produced Aluminium-Bronze Alloy  [PDF]
Uyime Donatus, Joseph Ajibade Omotoyinbo, Itopa Monday Momoh
Journal of Minerals and Materials Characterization and Engineering (JMMCE) , 2012, DOI: 10.4236/jmmce.2012.1110105
Abstract: This work studied the feasibility of producing a dual-phase aluminium bronze alloy and the use of selected treatments to manipulate the mechanical properties of the produced alloy using local techniques, as a potential replacement for con- ventional structural materials, particularly steels. Sand casting was used and was found to be effective based on its ad- vantages of low cost, ease of use and flexibility in the production of a dual-phase aluminium bronze alloy with pre-selected composition of 11% Al content. Cold deformation of 10 and 20% degrees and selected heat treatments were used on the cast alloy to influence its mechanical properties. The selected heat treatments are solution heat treat- ment, normalising, and ageing. The results showed that normalising gave the optimum mix of tested mechanical proper- ties with ultimate tensile strength in the range of 325 MPa, elongation of around 60% and Rockwell hardness values of 46.5 - 63.7 HRc, making this alloy suitable as alternatives to steel in low/medium strength structural applications.
Electrolytic surface hardening of steel,castiron and aluminium-bronze  [PDF]
Suhas Keshav Paknik a r
China Foundry , 2006,
Abstract: Electrolytic hardening process w as developed in USSR in the 1950s. The process w as developed but w as not com m ercially exploited. There is no evidence of w ork done on this process in India. The author has done this originalw ork applied to different m aterials like steel, castiron and alum inum -bronze.This paper gives details ofm icrostructuraltransform ations along w ith hardness value achieved. There is vitalscope for this process to becom e viable for surfacehardening and selective hardening ofsm allcom ponents.
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