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Joining of carbon steel AISI 1006 to aluminum alloy AA6061-T6 via friction spot joining technique

Ridha Munaf Hashim, Saad Mursal Luaibi, Abdullah Isam Tareq, Barrak Osamah Sabah, Hussein Sabah Khammass, Hussein Abbas Khammas

International Journal of Applied Mechanics and Engineering

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2022

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Vol. 27, no. 4

1--12

EN

This work aims to join sheets of carbon steel to aluminum alloy AA6061. A lap joint arrangement was used with a joint lap area of dimensions *25 25 mm . The joining procedure was carried out using a rotating tool of 10 mm shoulder diameter. Three process parameters, with three levels for each parameter, were selected to investigate their effects on joints quality. The parameter’s levels for each experiment were designed using the design of the experiment method (DOE). The results indicated that the two materials were joined by a mechanical interlock at an interface line, without formation of intermetallic compounds. The shear force of the joint reached an ultimate value of .4 82kN . The shear force of the joint improved by increasing plunging depth of the tool. Samples of minimum shear force value failed by a pull-outing aluminum metal from the carbon steel specimen. Samples of higher shear force value exhibited a shear mode of fracture. Increasing the rotating speed and decreasing pre-heating increased the process temperature.

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Friction spot lap joining of aluminum alloy AA6061 to pre-holed and threaded carbon steel AISI 1006

Ibrahim H. K., Hussein S. K., Jadee K. J.

International Journal of Applied Mechanics and Engineering

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2022

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Vol. 27, no. 1

67--77

EN

This work addresses to joining aluminum alloy AA6061 to carbon steel AISI 1006 sheets using the friction spot joining technique. The steel sheets were pre-holed and threaded with an internal M6 thread. The joining process was carried out by extruding the aluminum through the steel hole and thread using a rotating tool with friction between the tool and aluminum. Three process parameters were used: pre-heating time, rotating speed and plunging depth of the tool, with four levels for each parameter. The results indicated that the two materials joined by a micro-scale mechanical interlock at an interface line of a width ranged between 0.7 to ~ 2.5 mm. The joint’s shear force reached a minimum and maximum value of 2000 and 2500 N, respectively. The plunging depth was the most effective factor affecting the amount of the extruded aluminum and the joint’s shear force.

3

A new method for measurement the residual stresses in friction stir welding

Jweeg M.J., Hamdan Z.Kh., Majeed A.H., Resan K.K., Al-Waily M.

Archives of Materials Science and Engineering

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2021

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Vol. 112, nr 2

63--69

EN

Purpose: The residual stresses in different welding methods are fundemental problems to consider. Friction stir welding is one of a solid state joining process, it is economical in that it permits joining together different materials, the specimens in this method (FSW) have excellent properties of mechanical as proven by tensile, flextural and fatigue tests, also it is environmentally friendly process minimizes consumption of energy and generate no gasses or smoke. In friction stir welding , there are two kinds of generated residual stresses: tensile stress and compressive stress. So, this study measuring the residual stresses by using a new method for measuring residual stresses depends on tensile testing and stress concentration factor, this method is a simple, fast and low cost, also it is not need special device. Design/methodology/approach: In previous studies, several techniques were used to predict the value of residual stress and its location, such as destructive, semi-destructive, and non-destructive methods. In this study, a simple, new, and inexpensive way was used based on the tensile test and stress concentration of the friction stir welding (FSW). Findings: By comparing the results obtained with the previous studies using the X-ray method, with the current research, it was found that the results are good in detecting the location and value of the residual stress of friction stir welding. The value of discrepancy of the residual stress in the results between those obtained by the previous method and the current method was about 3 MPa. Research limitations/implications: There are many rotational and linear feeding speeds used in this type of welding. This research used two plates from 6061 AA with 3mm thickness, 100 mm width, and 200 mm length. The rotational speed used in friction stir welding was 1400 rpm, and the feeding speed was 40 mm/min. Practical implications: The residual stress obtained with the new method is 6.2 MPa, and this result approximates other known methods such as the X-ray method in previus studies. Originality/value: Using a new simple method for measuring residual stresses of friction stir welding depends on stress concentration factor and tensile testing. This method is fast and low cost , also it is not need specialized device, compared to other methods such as x-ray or hole drilling methods.

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Experimental investigation and modelling of hot forming B₄C/AA6061 low volume fraction reinforcement composites

Zheng K., Lin J., Wu G., Hall R. W., Dean T. A.

Journal of Theoretical and Applied Mechanics

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2018

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Vol. 56 nr 2

457--469

EN

This paper presents an experimental investigation of the hot deformation behaviour of 15% B₄C particle reinforced AA6061 matrix composites and the establishment of a novel corresponding unified and physically-based visco-plastic material model. The feasibility of hot forming of a metal matrix composite (MMC) with a low volume fraction reinforcement has been assessed by performing hot compression tests at different temperatures and strain rates. Examination of the obtained stress-strain relationships revealed the correlation between temperature and strain hardening extent. Forming at elevated temperatures enables obvious strain rate hardening and reasonably high ductility of the MMC. The developed unified material model includes evolution of dislocations resulting from plastic deformation, recovery and punching effect due to differential thermal expansion between matrix and reinforcement particles during non-steady state heating and plastic straining. Good agreement has been obtained between experimental and computed results. The proposed material model contributes greatly to a more thorough understanding of flow stress behaviour and microstructural evolution during the hot forming of MMCs.

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Synthesis and characterization of high entropy alloy (CrMnFeNiCu) reinforced AA6061 aluminium matrix composite

Prabakaran R. K., Naveen Sait A., Senthilkumar V.

Mechanics and Mechanical Engineering

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2017

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Vol. 21, nr 4

823--832

EN

Quinary High Entropy Alloy (HEA) system consists of Cr-Mn-Fe-Ni-Cu elements were prepared though powder metallurgy route. With varying wt. % of above prepared HEA powder as reinforcements, two different (10% and 20%) A6061 aluminium matrix composites were produced. Sinterablity of the composite powders was evaluated with different sintering time and temperature. The XRD results of HEA confirmed that the solid solution possess both FCC and BCC phases. Density, hardness and compressive strength of the fabricated composite were measured to evaluate the effect of HEA reinforcement. SEM micrographs of the composites were evaluated for the structure and to find the distribution of reinforcement particles.

6

Synthesis and characteristization of high entropy alloy (CrMnFeNiCu) reinforced AA6061 aluminium matrix composite

Prabakaran R. K., Naveen Sait A., Senthilkumar V.

Mechanics and Mechanical Engineering

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2017

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Vol. 21, nr 2

415--424

EN

Quinary High Entropy Alloy (HEA) system consists of Cr-Mn-Fe-Ni-Cu elements were prepared though powder metallurgy route. With varying wt. % of above prepared HEA powder as reinforcements, two different (10% and 20%) A6061 aluminium matrix composites were produced. Sinterablity of the composite powders was evaluated with different sintering time and temperature. The XRD results of HEA confirmed that the solid solution possess both FCC and BCC phases. Density, hardness and compressive strength of the fabricated composite were measured to evaluate the effect of HEA reinforcement. SEM micrographs of the composites were evaluated for the structure and to find the distribution of reinforcement particles.