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You searched for +publisher:"Nelson Mandela Metropolitan University" +contributor:("Els-Botes, A Dr"). Showing records 1 – 3 of 3 total matches.

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Nelson Mandela Metropolitan University

1. Mjali, Kadephi Vuyolwethu. Analysing the effect of FSP on MIG-laser hybrid welded 6082-T6 AA joints.

Degree: MTech, Faculty of Engineering, the Built Environment and Information Technology, 2007, Nelson Mandela Metropolitan University

Friction Stir Processing (FSP) of aluminium alloys has been used to modify and improve the microstructure and relevant properties of fusion welded aluminium alloys. The effect of FSP on MIG-Laser Hybrid (MLH) welded aluminium alloy 6082-T6 mechanical and microstructural properties has been studied in this research. The FSP process was used on 6mm thick aluminium alloy plates and a tool was designed specifically for FSP, and the effect of varying speeds was analysed before the final FSP welds were made. The effect of FSP was analysed by optical microscopy, tensile, microhardness and fatigue testing. The aim of the study was to determine whether the FSP process has a beneficial influence on the mechanical properties and metallurgical integrity of MIG-Laser Hybrid welded 6082-T6 aluminium alloy with varying gap tolerances. Three welding processes were compared, namely combined Friction Stir Processing on MIG-Laser hybrid process (FSP-MLH), MLH and Friction Stir Welding (FSW) as part of the analysis. (FSP was carried out on MLH components when it was found that FSP is not an entirely complete welding process but rather a finishing process per se.) The aim of this dissertation is to investigate the effects of the FSP process on the weld quality of MLH welded joints and also to compare this to individual processes like FSW and MLH. This investigation was undertaken in order to gain an understanding of the effect of these processes on fatigue performance and microhardness distribution on aluminium alloy 6082-T6 weld joints Advisors/Committee Members: Els-Botes, A Dr, Hattingh, D G Prof.

Subjects/Keywords: Friction stir welding

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6th Edition):

Mjali, K. V. (2007). Analysing the effect of FSP on MIG-laser hybrid welded 6082-T6 AA joints. (Masters Thesis). Nelson Mandela Metropolitan University. Retrieved from http://hdl.handle.net/10948/563

Chicago Manual of Style (16th Edition):

Mjali, Kadephi Vuyolwethu. “Analysing the effect of FSP on MIG-laser hybrid welded 6082-T6 AA joints.” 2007. Masters Thesis, Nelson Mandela Metropolitan University. Accessed February 29, 2020. http://hdl.handle.net/10948/563.

MLA Handbook (7th Edition):

Mjali, Kadephi Vuyolwethu. “Analysing the effect of FSP on MIG-laser hybrid welded 6082-T6 AA joints.” 2007. Web. 29 Feb 2020.

Vancouver:

Mjali KV. Analysing the effect of FSP on MIG-laser hybrid welded 6082-T6 AA joints. [Internet] [Masters thesis]. Nelson Mandela Metropolitan University; 2007. [cited 2020 Feb 29]. Available from: http://hdl.handle.net/10948/563.

Council of Science Editors:

Mjali KV. Analysing the effect of FSP on MIG-laser hybrid welded 6082-T6 AA joints. [Masters Thesis]. Nelson Mandela Metropolitan University; 2007. Available from: http://hdl.handle.net/10948/563


Nelson Mandela Metropolitan University

2. Makhanya, Lehlohonolo. Optimisation of cold rolling process parameters to improve surface quality of the AA 3003-H22 treadbright coils.

Degree: MTech, Faculty of Engineering, the Built Environment and Information Technology, Nelson Mandela Metropolitan University

The main objective of this dissertation was to investigate how cold rolling process parameters could be optimised to improve surface quality of the AA 3003 H22 treadbright coils. This treadbright product is one of Hulett Aluminium’s main products and is exported mainly to the North American market. One of its critical requirements is a defect-free bright surface. The literature review was conducted with particular focus on the effects of selected parameters or settings with respect to surface quality and a chapter outlining these aspects has been included. It was clear from the literature review that selected parameters do affect the surface quality and if adjusted accordingly can improve surface quality on treadbright coils. Subsequent chapters after the literature review outline how the tests were conducted, procedures followed and equipments used from the cold rolling machine to laboratories. Surface appearance results after each parameter was adjusted, showed that the surface quality did improve and even got better when other parameters like the colouring roll angle and percentage reduction were adjusted. Correct working limits within which each parameter would yield acceptable surface quality were also established. All experiments conducted had no influence on the microstructure of the metal as it remained the same throughout each experiment. The same has been found with the mechanical properties as percentage reductions experiments led to no change in tensile strength, proof strength and percentage elongation. In conclusion, this research has proved that cold rolling process parameters selected did affect the product surface quality. If controlled they can be used to optimise the surface quality on the treadbright product as required by Hulett Aluminium and its customers Advisors/Committee Members: Els-Botes, A Dr, Taljaard, P, Hattingh, D G Prof.

Subjects/Keywords: Aluminum alloys

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6th Edition):

Makhanya, L. (n.d.). Optimisation of cold rolling process parameters to improve surface quality of the AA 3003-H22 treadbright coils. (Masters Thesis). Nelson Mandela Metropolitan University. Retrieved from http://hdl.handle.net/10948/554

Note: this citation may be lacking information needed for this citation format:
No year of publication.

Chicago Manual of Style (16th Edition):

Makhanya, Lehlohonolo. “Optimisation of cold rolling process parameters to improve surface quality of the AA 3003-H22 treadbright coils.” Masters Thesis, Nelson Mandela Metropolitan University. Accessed February 29, 2020. http://hdl.handle.net/10948/554.

Note: this citation may be lacking information needed for this citation format:
No year of publication.

MLA Handbook (7th Edition):

Makhanya, Lehlohonolo. “Optimisation of cold rolling process parameters to improve surface quality of the AA 3003-H22 treadbright coils.” Web. 29 Feb 2020.

Note: this citation may be lacking information needed for this citation format:
No year of publication.

Vancouver:

Makhanya L. Optimisation of cold rolling process parameters to improve surface quality of the AA 3003-H22 treadbright coils. [Internet] [Masters thesis]. Nelson Mandela Metropolitan University; [cited 2020 Feb 29]. Available from: http://hdl.handle.net/10948/554.

Note: this citation may be lacking information needed for this citation format:
No year of publication.

Council of Science Editors:

Makhanya L. Optimisation of cold rolling process parameters to improve surface quality of the AA 3003-H22 treadbright coils. [Masters Thesis]. Nelson Mandela Metropolitan University; Available from: http://hdl.handle.net/10948/554

Note: this citation may be lacking information needed for this citation format:
No year of publication.


Nelson Mandela Metropolitan University

3. Von Wielligh, Louis George. Characterizing the influence of process variables in laser cladding Al-20WT%Si onto an Aluminium Substrate.

Degree: MTech, Faculty of Engineering, the Built Environment and Information Technology, Nelson Mandela Metropolitan University

The research investigated the application of continuous coaxial laser cladding by powder injection as a surface treatment or coating process. The investigation aimed to establish the relationship between a change in the main laser cladding process variables and the geometry and characteristics of an Al-20wt-Si single pass clad layer formed on an Al 1370-F substrate using a Nd:YAG laser. The main process variables considered were: laser power, laser scanning velocity and the powder feed rate. The relationship between a change in the main laser cladding process variables and the geometry and characteristics of the clad layer was established by statistically analysing the variation in the process response with a change in the main laser cladding process variables. The process variables were varied based on a full-factorial, experimentally optimized test matrix. The clad geometry which is mainly defined by: the clad height, width, clad aspect ratio, depth of alloy penetration, and the clad root angle/wetting angle was investigated. In addition to the clad geometry several clad characteristics were investigated such as the dilution of the clad layer in the substrate material, the Vickers microhardness and microstructure of the clad crosssection, the powder efficiency of the process and the amount of visible defects. The study successfully established the relationship between the main laser cladding process variables and the clad geometry and characteristics. The secondary objective of establishing a suitable processing window by considering the relationship mentioned above was only partially met since it is believed that further refinement of the experimental cladding test setup and therefore also the experimental variable test levels is required Advisors/Committee Members: Hattingh, D G Prof, Els-Botes, A Dr.

Subjects/Keywords: Lasers  – Industrial applications; Metal cladding

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6th Edition):

Von Wielligh, L. G. (n.d.). Characterizing the influence of process variables in laser cladding Al-20WT%Si onto an Aluminium Substrate. (Masters Thesis). Nelson Mandela Metropolitan University. Retrieved from http://hdl.handle.net/10948/721

Note: this citation may be lacking information needed for this citation format:
No year of publication.

Chicago Manual of Style (16th Edition):

Von Wielligh, Louis George. “Characterizing the influence of process variables in laser cladding Al-20WT%Si onto an Aluminium Substrate.” Masters Thesis, Nelson Mandela Metropolitan University. Accessed February 29, 2020. http://hdl.handle.net/10948/721.

Note: this citation may be lacking information needed for this citation format:
No year of publication.

MLA Handbook (7th Edition):

Von Wielligh, Louis George. “Characterizing the influence of process variables in laser cladding Al-20WT%Si onto an Aluminium Substrate.” Web. 29 Feb 2020.

Note: this citation may be lacking information needed for this citation format:
No year of publication.

Vancouver:

Von Wielligh LG. Characterizing the influence of process variables in laser cladding Al-20WT%Si onto an Aluminium Substrate. [Internet] [Masters thesis]. Nelson Mandela Metropolitan University; [cited 2020 Feb 29]. Available from: http://hdl.handle.net/10948/721.

Note: this citation may be lacking information needed for this citation format:
No year of publication.

Council of Science Editors:

Von Wielligh LG. Characterizing the influence of process variables in laser cladding Al-20WT%Si onto an Aluminium Substrate. [Masters Thesis]. Nelson Mandela Metropolitan University; Available from: http://hdl.handle.net/10948/721

Note: this citation may be lacking information needed for this citation format:
No year of publication.

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