Advanced Applications in Manufacturing Enginering, 2019
The chapter introduces the Small and Medium Enterprises (SMEs) coping model or strategy for opera... more The chapter introduces the Small and Medium Enterprises (SMEs) coping model or strategy for operation advancement in manufacturing technology. Advances in manufacturing calls for how the small and medium scale industries could be salvaged, sustained, and prevented from folding up as they could no longer cope with the trends in manufacturing sustainability. They could not stand competitively with fast growing technology, hence leading to low patronage of their products and low investment turn over. In view of this, this chapter formulates a strategy that assists these SMEs in making decision that are based on market feelings and intuition in a structured approach with the use of limited available capital or resources. The chapter also considers approaches in advanced manufacturing technology with appropriate manufacturability and operation concepts for establishing the right choice of manufacturing to adopt for SMEs with little or no change in their production floors and facilities. ...
The weldability of the AA2024-T3 and AZ31 Mg alloys was investigated using the modified friction ... more The weldability of the AA2024-T3 and AZ31 Mg alloys was investigated using the modified friction stir clinching-brazing (MFSC-B) and probe-less friction stir spot brazing (PFSSB) processes. A 50 µm thick Zn foil-interlayer was sandwiched between the dissimilar base materials for the welding processes. The mechanical, microstructure, and weld-fracture behaviors of all joints were studied and compared. Zn-rich interdiffusion-aided lamellar and blocky structures are found at the brazed region/zone of the AA2024-T3/Zn/AZ31 joint irrespective of the welding process due to the sole influence of heat input at the zone. The differential flow in the MFSC-B joint enforces significant inter-material mingling, better distribution of Zn, and more subgrains/dislocation density at the joint as compared to the PFSSB joint. The interlayer inhibited the creation of the β-Al3Mg2 phase while the γ-Al12Mg17 phase could not be prevented in the AA2024-T3/Zn/AZ31 joints due to tool-induced atomic collision and diffusion–reaction mechanisms. Improved tensile/shear failure load is found in the MFSC-B joint (4369 N) as related to their PFSSB counterpart (3018 N) due to improved material flow (intermixing), and intense dislocation density. The MFSC-B process is thus recommended for dissimilar joining of Mg and Al alloys.
Advanced Applications in Manufacturing Enginering, 2019
The chapter introduces the Small and Medium Enterprises (SMEs) coping model or strategy for opera... more The chapter introduces the Small and Medium Enterprises (SMEs) coping model or strategy for operation advancement in manufacturing technology. Advances in manufacturing calls for how the small and medium scale industries could be salvaged, sustained, and prevented from folding up as they could no longer cope with the trends in manufacturing sustainability. They could not stand competitively with fast growing technology, hence leading to low patronage of their products and low investment turn over. In view of this, this chapter formulates a strategy that assists these SMEs in making decision that are based on market feelings and intuition in a structured approach with the use of limited available capital or resources. The chapter also considers approaches in advanced manufacturing technology with appropriate manufacturability and operation concepts for establishing the right choice of manufacturing to adopt for SMEs with little or no change in their production floors and facilities. ...
A hydraulic press machine comprising of the frame, cylinder, hand pump, and pressure gauge was de... more A hydraulic press machine comprising of the frame, cylinder, hand pump, and pressure gauge was designed, fabricated, and evaluated. The machine is manually operated and the frame was modeled using the Solidwork application software 2018 version. The maximum stress, maximum displacement, maximum strain, and factor of safety of the machine are 97.09 MPa, 0.337696 mm, 0.000361326, and 2.32 respectively. The performance of the developed machine was successfully carried out by using it to mould clay of different sieve sizes (0.6-4.75 mm) into crucible form with an applied maximum pressure of 100 bar. The results showed that the smaller the size of the sieve, the lower the pressure required for compaction, as a result, the hydraulic press designed is effective for clay compaction and the design is safe. The machine which was fabricated with local materials will enhance the production of suitable crucibles, thereby, reducing the over-reliance on the foreign crucible by small and medium sca...
Flexible and digital manufacturing technologies like additive manufacturing (AM) have evolved as ... more Flexible and digital manufacturing technologies like additive manufacturing (AM) have evolved as the future of modern manufacturing with the capability of obtaining multi-dimensional components and material functionality improvement. In the past decade, the additive manufacturing of steel has advanced into an effective approach for controlling local microstructure and fabricating hybrid build with tailored performance. As an emerging technology, there are still some challenges in the additive manufacturing of steel that need to be circumvented in order to attain the full potentials of this novel technology. This review paper examines the current state of additively manufactured steel as well as the associated microstructure, mechanical properties, and corrosion of as-built steel. An insight into further and future research directions is provided.
Design freedom, complex geometry fabrication capability, minimal parts assembly and excellent mat... more Design freedom, complex geometry fabrication capability, minimal parts assembly and excellent material utilization attributes of additive manufacturing processes have provided a leverage ground for the development of functional engineering steel parts in the manufacturing industries. Despite the good attributes of additive manufacturing technology, there are still some local and inherent defects of as-built steel parts that can jeopardize the overall integrity of structural steel components. This review paper provides the associated defects of as-built steel and summarizes the post-manufacturing strategies being deployed to mitigate the severity of as-built steel defects. The microstructural and mechanical responses of some specific as-built steel under different fabrication conditions or additive manufacturing techniques are also summarized in this paper.
Abstract This paper studies the friction stir spot welding of AA2024-T3/AA7075-T6 Al alloys in th... more Abstract This paper studies the friction stir spot welding of AA2024-T3/AA7075-T6 Al alloys in the ambient and underwater environments by clarifying the nugget features, microstructure, fracture and mechanical properties of the joints. The results show that the water-cooling medium exhibits a significant heat absorption capacity in the AA2024-T3/AA7075-T6 welded joint. Nugget features such as stir zone width, circular imprints, average grain sizes, and angular inter-material hooking are reduced by the water-cooling effect in the joints. Narrower whitish (intercalated structures) bands are formed in the underwater joints while Mg2Si and Al2CuMg precipitates are formed in the ambient and the underwater welded joints respectively. An increase in tool rotational speed (600–1400 rpm) and plunge depth (0.1–0.5 mm) increases the tensile-shear force of the welded AA2024-T3/AA7075-T6 joints in both the ambient and underwater environments. The maximum tensile-shear forces of 5900 N and 6700 N were obtained in the ambient and the underwater welds respectively.
Advanced Applications in Manufacturing Enginering, 2019
The chapter introduces the Small and Medium Enterprises (SMEs) coping model or strategy for opera... more The chapter introduces the Small and Medium Enterprises (SMEs) coping model or strategy for operation advancement in manufacturing technology. Advances in manufacturing calls for how the small and medium scale industries could be salvaged, sustained, and prevented from folding up as they could no longer cope with the trends in manufacturing sustainability. They could not stand competitively with fast growing technology, hence leading to low patronage of their products and low investment turn over. In view of this, this chapter formulates a strategy that assists these SMEs in making decision that are based on market feelings and intuition in a structured approach with the use of limited available capital or resources. The chapter also considers approaches in advanced manufacturing technology with appropriate manufacturability and operation concepts for establishing the right choice of manufacturing to adopt for SMEs with little or no change in their production floors and facilities. ...
The weldability of the AA2024-T3 and AZ31 Mg alloys was investigated using the modified friction ... more The weldability of the AA2024-T3 and AZ31 Mg alloys was investigated using the modified friction stir clinching-brazing (MFSC-B) and probe-less friction stir spot brazing (PFSSB) processes. A 50 µm thick Zn foil-interlayer was sandwiched between the dissimilar base materials for the welding processes. The mechanical, microstructure, and weld-fracture behaviors of all joints were studied and compared. Zn-rich interdiffusion-aided lamellar and blocky structures are found at the brazed region/zone of the AA2024-T3/Zn/AZ31 joint irrespective of the welding process due to the sole influence of heat input at the zone. The differential flow in the MFSC-B joint enforces significant inter-material mingling, better distribution of Zn, and more subgrains/dislocation density at the joint as compared to the PFSSB joint. The interlayer inhibited the creation of the β-Al3Mg2 phase while the γ-Al12Mg17 phase could not be prevented in the AA2024-T3/Zn/AZ31 joints due to tool-induced atomic collision and diffusion–reaction mechanisms. Improved tensile/shear failure load is found in the MFSC-B joint (4369 N) as related to their PFSSB counterpart (3018 N) due to improved material flow (intermixing), and intense dislocation density. The MFSC-B process is thus recommended for dissimilar joining of Mg and Al alloys.
Advanced Applications in Manufacturing Enginering, 2019
The chapter introduces the Small and Medium Enterprises (SMEs) coping model or strategy for opera... more The chapter introduces the Small and Medium Enterprises (SMEs) coping model or strategy for operation advancement in manufacturing technology. Advances in manufacturing calls for how the small and medium scale industries could be salvaged, sustained, and prevented from folding up as they could no longer cope with the trends in manufacturing sustainability. They could not stand competitively with fast growing technology, hence leading to low patronage of their products and low investment turn over. In view of this, this chapter formulates a strategy that assists these SMEs in making decision that are based on market feelings and intuition in a structured approach with the use of limited available capital or resources. The chapter also considers approaches in advanced manufacturing technology with appropriate manufacturability and operation concepts for establishing the right choice of manufacturing to adopt for SMEs with little or no change in their production floors and facilities. ...
A hydraulic press machine comprising of the frame, cylinder, hand pump, and pressure gauge was de... more A hydraulic press machine comprising of the frame, cylinder, hand pump, and pressure gauge was designed, fabricated, and evaluated. The machine is manually operated and the frame was modeled using the Solidwork application software 2018 version. The maximum stress, maximum displacement, maximum strain, and factor of safety of the machine are 97.09 MPa, 0.337696 mm, 0.000361326, and 2.32 respectively. The performance of the developed machine was successfully carried out by using it to mould clay of different sieve sizes (0.6-4.75 mm) into crucible form with an applied maximum pressure of 100 bar. The results showed that the smaller the size of the sieve, the lower the pressure required for compaction, as a result, the hydraulic press designed is effective for clay compaction and the design is safe. The machine which was fabricated with local materials will enhance the production of suitable crucibles, thereby, reducing the over-reliance on the foreign crucible by small and medium sca...
Flexible and digital manufacturing technologies like additive manufacturing (AM) have evolved as ... more Flexible and digital manufacturing technologies like additive manufacturing (AM) have evolved as the future of modern manufacturing with the capability of obtaining multi-dimensional components and material functionality improvement. In the past decade, the additive manufacturing of steel has advanced into an effective approach for controlling local microstructure and fabricating hybrid build with tailored performance. As an emerging technology, there are still some challenges in the additive manufacturing of steel that need to be circumvented in order to attain the full potentials of this novel technology. This review paper examines the current state of additively manufactured steel as well as the associated microstructure, mechanical properties, and corrosion of as-built steel. An insight into further and future research directions is provided.
Design freedom, complex geometry fabrication capability, minimal parts assembly and excellent mat... more Design freedom, complex geometry fabrication capability, minimal parts assembly and excellent material utilization attributes of additive manufacturing processes have provided a leverage ground for the development of functional engineering steel parts in the manufacturing industries. Despite the good attributes of additive manufacturing technology, there are still some local and inherent defects of as-built steel parts that can jeopardize the overall integrity of structural steel components. This review paper provides the associated defects of as-built steel and summarizes the post-manufacturing strategies being deployed to mitigate the severity of as-built steel defects. The microstructural and mechanical responses of some specific as-built steel under different fabrication conditions or additive manufacturing techniques are also summarized in this paper.
Abstract This paper studies the friction stir spot welding of AA2024-T3/AA7075-T6 Al alloys in th... more Abstract This paper studies the friction stir spot welding of AA2024-T3/AA7075-T6 Al alloys in the ambient and underwater environments by clarifying the nugget features, microstructure, fracture and mechanical properties of the joints. The results show that the water-cooling medium exhibits a significant heat absorption capacity in the AA2024-T3/AA7075-T6 welded joint. Nugget features such as stir zone width, circular imprints, average grain sizes, and angular inter-material hooking are reduced by the water-cooling effect in the joints. Narrower whitish (intercalated structures) bands are formed in the underwater joints while Mg2Si and Al2CuMg precipitates are formed in the ambient and the underwater welded joints respectively. An increase in tool rotational speed (600–1400 rpm) and plunge depth (0.1–0.5 mm) increases the tensile-shear force of the welded AA2024-T3/AA7075-T6 joints in both the ambient and underwater environments. The maximum tensile-shear forces of 5900 N and 6700 N were obtained in the ambient and the underwater welds respectively.
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