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1

Impact of pouring temperature on the mechanical properties of Al5.9Cu1.9Mg alloy

Akhyar Akhyar, Iswanto P.T., Malau V.

Archives of Materials Science and Engineering

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2022

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Vol. 113, nr 2

49--55

EN

Purpose: This experiment aims to determine the influence of pouring temperature on the hardness, impact energy, tensile strength, and changes in the microstructure of the Al-5.9Cu- 1.9Mg alloy. Design/methodology/approach: A total of three samples of aluminium alloy were heated to 688, 738, and 788°C, and poured into permanent moulds in form of plates at a constant temperature of 220°C. The cast products are machined according to testing standards for hardness, impact tests, and tensile strength. Findings: The results showed that the metal hardness and impact energy increased to 103 BHN and 7.48 J at 788°C, respectively, while the tensile strength rises as the temperatures decreases. Furthermore, the changes in the microstructure were affected, which indicated that all the properties of the aluminium alloy were influenced by the variations in temperature. Research limitations/implications: During the metal casting process, only three different pouring temperatures affected the properties of the metal alloy, therefore, there is a need for more variations. Practical implications: The proposed pouring temperature parameter is an important condition for industrial foundry applications to obtain the right product for use in a machining element. Originality/value: This research shows the influence of the difference in pouring temperatures on the properties of metal alloys due to casting, where they will be adapted for a particular use.

2

Effect of cold rolling on microstructure and hardness of annealed Al-Cu-Mg alloy

Liu Fei, Liu Zhiyi, He Guangyu

Archives of Civil and Mechanical Engineering

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2022

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Vol. 22, no. 2

art. no. e64, 1--17

EN

The dislocation slips during the hot- and cold-rolling processes, the texture evolution and the Goss-oriented grain refinement during the annealing of the Al-Cu-Mg alloy were investigated using optical microscope (OM), scanning electron microscope (SEM), electron back-scatter diffraction (EBSD), transmission electron microscope (TEM) and X-ray diffraction (XRD). Results shown that {111} <110> octahedral slip systems and {110} <111> non-octahedral slip systems can be activated during the hot- and cold-rolling. When the dislocation slips in {111} planes are suppressed, the cross-slip from the {111} planes to the {110} planes can be activated to coordinate deformation. The strain gradients between the adjacent grains of the alloy with the large cold rolling reduction during annealing are dramatically decreased by the strain homogenization, which suppresses the growth of {110} < 001 > Goss-oriented grains. The activation of {110} <111> slip systems may be led to the decrease of the intensity of {112} <111> Copper texture, and the effect of {110} <111> slip systems on the evolution of {001} < 100 > Cube texture is very small. With the increase of the cold rolling reduction and annealing temperature, the hardness of the annealed and rolled Al-Cu-Mg alloy all increases, strain hardening and grain refinement are responsible for the enhanced hardness.

3

Evolution of Goss texture in an Al–Cu–Mg alloy during cold rolling

Zhao Qi, Liu Zhiyi, Hu Yangcheng, Li Shasha, Bai Song

Archives of Civil and Mechanical Engineering

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2020

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Vol. 20, no. 1

340--354

EN

Evolution of Goss texture in an Al–Cu–Mg alloy during cold rolling was investigated by three-dimensional orientation distribution functions, electron back-scattered diffraction and transmission electron microscopy. The results showed that with increasing reduction from 23.7 to 80%, Goss textures gradually transformed into Brass texture through the activation of sole {111}<110> slip systems. When rolling reduction further increased from 80 to 86.3%, Goss texture rather than Brass started to rotate towards Copper and S components. The formation of Copper and S textures at these high reductions was attributed to the activation of {110}<110> and {001}<110> non-octahedral slip systems.

4

De-Lubrication Behavior Of Novel EBS Based Admixed Lubricant In Aluminum P/M Alloy

Oh M. C., Seok H., Kim H. J., Ahn B.

Archives of Metallurgy and Materials

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2015

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Vol. 60, iss. 2B

1427--1431

EN

The objective of the present research is to develop a novel lubricant for Al-Cu-Mg P/M alloy and to address the effects of the lubricant and compaction pressure on sintered properties. A lubricant mixture consisting of Ethylene Bis Stearamide, Zn-Stearate, and fatty acid was newly developed in this study, and the de-lubrication behavior was compared with that of other commercial lubricants, such as Ethylene Bis Stearamide, Zn-Stearate, and Al-Stearate. Density and transverse rupture strength of sintered materials with each lubricant were examined, respectively. The microstructural analysis was conducted using optical microscope.

5

Effect of temperature and strain rate on friction factor during hot deformation of Al-Mn and Al-Cu-Mg Al-alloys

Petrov P., Gnevashev D., Dubinchin A., Petrov M., Solotych V., Eiesland J. W.

Computer Methods in Materials Science

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2009

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Vol. 9, No. 1

55-60

EN

Massive hot forging of any aluminium alloy can be performed with the help of several types of metal-forming machines, namely hydraulic press, mechanical press, screw press etc. Applying one of these machines allows production of either typical forgings or near net shape forgings. Anyway, there is a technological parameter which has a strong influence the quality of a forging made of Al-alloy. This is the composition of lubricant. The choice of a lubricant for forging is major task, especially in case of aluminium alloys deformation. The efficiency of any lubricant can be estimated by at least three criteria: 1) the lubricant should have good tribological properties; 2) the lubricant should have good heat-shielding properties; 3) the lubricant should produce little or no smoke. The paper is linked to the investigation of the effect of temperature as well as strain rate on lubricants for massive hot forging. Friction factor was chosen as one of the criteria for the estimation of the effects mentioned. Wide range of temperatures was observed. The research on friction has been done for Al-Mn and Al-Cu-Mg aluminium alloys. In this connection, physical and numerical investigation of friction performed. The condition of experimental investigation corresponded to the forging process of Al-alloys with the help of the hydraulic and screw press as well. The ring upsetting technique with combination of FE-simulation was chosen for investigation of the effect of temperature and strain rate on friction factor value. The regressions for the relationship between friction factor and temperature as well as strain rate for all lubricant under study have been obtained. Some practical recommendations were given.

PL

Tematem artykułu są badania wpływu temperatury oraz prędkości odkształcenia na własności smarów w procesie kucia matrycowego na gorąco. Wspólczynnik tarcia został wybrany jako jedno z kryteriów estymacji analizowanego efektu. Badania tarcia wykonano dla stopów aluminium Al-Mg oraz Al-Cu-Mg w podwyższonej temperaturze. Zachowanie się smarów analizowano w zakresie temperatur 200-470°C. Przeprowadzono fizyczne oraz numeryczne symulacje. Badania doświadczalne wykonane zostały dla procesu kucia stopów aluminium na prasach hydraulicznej i śrubowej. Natomiast do analizy numerycznej wpływu temperatury i prędkości odkształcenia na współczynnik tarcia wybrano proces spęczania pierścieni symulowany przy użyciu metody elementów skończonych. Ostatecznie otrzymano zależności regresyjne pomiędzy analizowanymi parametrami, które zostały przedstawione w artykule wraz z pewnymi praktycznymi wskazówkami.

6

Generalized approach to the choice of lubricant for hot isothermal forging of aluminium alloys

Petrov P.

Computer Methods in Materials Science

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2007

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Vol. 7, No. 1

106-111

EN

Isothermal forging is a technological process of hot bulk forging which is related to definite temperatures of dies and workpiece heating. Usually, isothermal forging is performed with the help of low-velocity forging equipment like hydraulic presses. So that the maximum value of die velocity is not more than 5 mm/s. To avoid die chilling the dies are heated up to approximately the same temperature as the workpiece. In this range, conventional die materials for hot bulk forging cannot undergo the significant loss of strength or hardness. So, special tool materials should be applied for dies production. The development of any technological process of bulk forging and namely isothermal one requires the solution of the following tasks: 1) choose the forging method or forming process (forging with/without flash); 2) design a forging part in accordance with a machined part; 3) determine the necessary amount of forging operations; 4) determine the size and shape of workpiece; 5) design forging dies; 6) choose the suitable press-forging equipment and lubrication; 7) try out experimentally the developed technology and if necessary make some modifications. In most cases, the application of forging in isothermal conditions means the production of a near net shape forging. Design of near net shape forging part according to a machined one can be carried out with the help of some recommendations which are based on practical experience of forging. One of the technological parameters which has a strong influence the quality of a near net shape forging is the type of lubricant. The choice of a lubricant for isothermal forging is major task, especially in case of aluminium alloys deformation. The isothermal forging of Al-alloys belongs to the forging processes in which the slight increase in contact friction affects on the material flow, the quality of the forgings and gives rise to increase in deformation load. The efficiency of any lubricant can be estimated by at least three criteria: 1) the lubricant should have good tribological properties; 2) the lubricant should have good heat-shielding properties; 3) the lubricant should produce little or no smoke. So that, some laboratory tests should be carried out. The present paper is a generalization of the results which were obtained for the last three years. It implies the investigations of interfacial friction in hot isothermal deformation of such non-ferrous material as Al-Mn, Al-Mg, Al-Cu-Mg and Al-Cu-Mg-Fe-Ni aluminium alloys. Two completely different types of lubricant were used for the research on. Wide range of temperatures was observed. Moreover, the hydraulic press and screw press were used for the deformation of the samples of aluminium alloys under study. The tribological properties of lubricants were determined with the help of ring upsetting technique. The sets of calibration curves were drawn. Each set of calibration curves corresponds to the definite type of aluminium alloy as well as definite conditions of deformation. Some practical recommendations were given.

PL

Uogólnienie wyników uzyskanych na przestrzeni czterech nich lat (Petrov et al., 2003, 2004, 2005, 2006) z zakresu i wpływu tarcia międzyfazowego podczas odkształcenia na gorąco jest tematem niniejszej publikacji. W pracy analizowano materiały nieżelazne na bazie aluminium: Al-Mn (AA3003), Al-Mg (A95456), Al-Cu-Mg (AA2024) i Al-Cu-Mg-Fe-Ni (A92618). Analizę prowadzono dla szerokiego zakresu temperatur i dwóch różnych smarów z wykorzystaniem prasy hydraulicznej. Własności trybologiczne wykorzystanych smarów określono bazując na wynikach spęczania pierścieni. W pracy wykreślono krzywe wzorcowe odpowiadające konkretnym warunkom odkształcenia i danemu stopowi Al. Zamieszczono również uwagi praktyczne.