Zn-Al-Cu alloys are predominantly used due to their tribological properties. One of the crucial issues related to the use of Zn-Al alloys is their dimensional instability. Partial replacement of copper with titanium greatly contributes to the reduction of the dimensional instability issue. The study involved the ZnAl40Cu1.5Ti1.5 alloy. In this work, microstructure and wear properties of ZnAl40Cu1.5Ti1.5 alloy were studied in both as-cast and heat treated conditions. The heat treatment was performed by solution treatment at a temperature of 385°C for 24 hours, quenching in cold water and artificial aging at 125°C for 3 hours. The hardness tests enabled to specify the optimum ageing time span, which amounts to 3 hours. Wear tests indicated that the ZnAl40Cu1.5Ti1.5 alloy is characterized with high wear resistance. It was also observed that the applied heat treatment increases the wear resistance of the experimental alloy.
2 May 2014 in Materialwissenschaft und Werkstofftechnik
In this paper, a novel, composite material is proposed based on ferromagnetic wires immersed in a polymer that is well suited for 3D printing. The magnetic properties of this material are examined using FEM and compared with the properties of a more traditional composite based on magnetic powder. For a 50% ferromagnetic volume in the material, the proposed composite has a 67% higher value of saturation magnetic flux density and 87% higher value of maximum permeability, compared with the powder-based material. The authors believe that the proposed material could be used in the manufacturing of small electromechanical devices such as energy harvesters, thus vastly widening the possible fields of application related to 3D printing techniques.
1 March 2016 in Archives of Metallurgy and Materials
Zn-Al-Cu alloys are used primarily because of their tribological properties as an alternative material for bronze, cast iron and aluminum alloy bearings and as a construction material. Particularly interesting are high aluminum zinc alloys. Monoeutectic zinc and aluminum alloys are characterized by the highest hardness, tensile strength and wear resistance of all of the zinc alloys. A significant problem with the use of the Zn-Al-Cu alloys is their insufficient resistance to electrochemical corrosion. Properties of Zn-Al-Cu alloys can be improved by heat treatment. The purpose of examination was to determine the effect of heat treatment (aging at various temperatures) on the microstructure and corrosion resistance of the ZnAl40Cu3 alloy. The scope of the examination included: structural examinations, determination of hardness using Brinell’s method and corrosion resistance examinations. Ageing at higher temperatures causes a creation of areas where is an eutectoid mixture. The study showed that ageing causes a decrease in hardness of ZnAl40Cu3 alloy. This decrease is even greater, when the temperature of ageing is lower. The studies have shown a significant influence of ageing on the corrosion resistance of the alloy ZnAl40Cu3. Maximum corrosion resistance were characterized by the sample after ageing at higher temperatures.
1 September 2016 in Archives of Metallurgy and Materials
The influence of solution heat treatment at 385°C over 10 h with cooling in water on the structure, hardness and strength of the ZnAl22Cu3 eutectoid alloy is presented in the paper. The eutectoid ZnAl22Cu3 alloy is characterized by a dendritic structure. Dendrites are composed of a supersaturated solid solution of Al in Zn. In the interdendritic spaces a eutectoid mixture is present, with an absence of the ε (CuZn4) phase. Solution heat treatment of the ZnAl22Cu3 alloy causes the occurrence of precipitates rich in Zn and Cu, possibly ε phase. Solution heat treatment at 385°C initially causes a significant decrease of the alloy hardness, although longer solution heat treatment causes a significant increase of the hardness as compared to the as-cast alloy.