Al-Cu Composite’s Springback in Micro Deep Drawing

With the recent technological trend of miniaturization in manufacturing industries, the rise of micro forming operations such as micro deep drawing (MDD) is inevitable. On the other hand, the need of more advanced materials is essential to accommodate various applications. However, a major problem are size effects that make micro scale operations challenging. One of the most important behaviors affected by size effects is the springback phenomenon, which is the tendency of a deformed material to go back to its original shape. Springback can affect dimensional accuracy, which is very important in micro products. Thus, this paper investigated the springback behavior of Al-Cu composite in MDD operations. Micro cups were fabricated from blank sheet specimens using an MDD apparatus with variation of annealing holding time. The springback values were measured and compared to each other. The results showed that different grain sizes lead to variation in the amount of springback. However, unlike in single-element materials, the amount of springback in Al-Cu composite is not only related to the thickness to grain size (t/d) ratio. Another factor, i.e., the existence of an interfacial region between layers, alters the mechanical behavior of the composite

Al-Cu Composite’s Springback in Micro Deep Drawing

With the recent technological trend of miniaturization in manufacturing industries, the rise of micro forming operations such as micro deep drawing (MDD) is inevitable. On the other hand, the need of more advanced materials is essential to accommodate various applications. However, a major problem are size effects that make micro scale operations challenging. One of the most important behaviors affected by size effects is the springback phenomenon, which is the tendency of a deformed material to go back to its original shape. Springback can affect dimensional accuracy, which is very important in micro products. Thus, this paper investigated the springback behavior of Al-Cu composite in MDD operations. Micro cups were fabricated from blank sheet specimens using an MDD apparatus with variation of annealing holding time. The springback values were measured and compared to each other. The results showed that different grain sizes lead to variation in the amount of springback. However, unlike in single-element materials, the amount of springback in Al-Cu composite is not only related to the thickness to grain size (t/d) ratio. Another factor, i.e., the existence of an interfacial region between layers, alters the mechanical behavior of the composite

Enhanced performance of micro deep drawing through the application of TiO2 nanolubricant and graphene lubricants on SUS 301 stainless steel foil

first_pagesettingsOrder Article Reprints Open AccessArticle Enhanced Performance of Micro Deep Drawing through the Application of TiO2 Nanolubricant and Graphene Lubricants on SUS 301 Stainless Steel Foil by Di Pan 1ORCID,Guangqing Zhang 1,Fanghui Jia 1,Yao Lu 2,Jun Wang 2,Zhou Li 3,Lianjie Li 4,Ming Yang 5ORCID andZhengyi Jiang 1,* 1 School of Mechanical, Materials, Mechatronic and Biomedical Engineering, Wollongong, NSW 2522, Australia 2 Welding Engineering and Laser Processing Centre, Cranfield University, Bedfordshire MK43 0AL, UK 3 College of Mechanical and Electrical Engineering, Central South University, Changsha 410083, China 4 School of Intelligent Manufacturing and Control Engineering, Shanghai Polytechnic University, Shanghai 201209, China 5 Graduate School of System Design, Tokyo Metropolitan University, Hino, Tokyo 191-0055, Japan * Author to whom correspondence should be addressed. Processes 2023, 11(10), 3042; https://doi.org/10.3390/pr11103042 Received: 2 September 2023 / Revised: 17 October 2023 / Accepted: 20 October 2023 / Published: 23 October 2023 (This article belongs to the Special Issue Processing, Manufacturing and Properties of Metal and Alloys) Downloadkeyboard_arrow_down Browse Figures Versions Notes Abstract In recent years, the quest for effective lubrication in micro deep drawing (MDD) has seen promising advancements. In this study, the influence of TiO2 nanolubricants and graphene lubricants on the performance of 301 stainless steel foil in MDD is examined. The MDD undergoes an extensive evaluation of various lubrication conditions, including dry, TiO2 nanolubricant, graphene lubricant at concentrations of 2.5 mg/mL, 5.0 mg/mL, and 10.0 mg/mL, as well as combined applications of TiO2 and graphene lubricants. Utilising a 5.0 mg/mL graphene lubricant together with TiO2 nanolubricants led to a significant reduction in drawing force, highlighting the synergistic efficacy of this combined lubricant. A pronounced enhancement in the consistency of the produced microcups was also attained. These results emphasise the promise of TiO2 nanolubricant and graphene lubricants in optimising the MDD process

Ex situ analysis of high-strength quenched and micro-alloyed steel during austenitising bending process: numerical simulation and experimental investigation

This paper compares the microstructure and mechanical evolution in a high-strength quenched and micro-alloyed steel during the austenitising bending process. Simulation results indicated a new finding that the stress neutral layer (SNL) tends to move to the tension zone during straining. The hardness gradient detected from the centre to compression/tension zones was resulted from comprehensive factors: First of all, the location of SNL revealed a prominent impact on strength. Second, the dislocation accumulation would be responsible for the hardness gradient on the surfaces. In addition, the overall strength decrease during straining was mainly ascribed to integrated effects of dynamic recovery (DRV) and dynamic recrystallisation (DRX). Apart from that, overall smaller martensite packet size and coarser prior austenite grains resulted in the increased hardness value at a lower bending degree. Also, the high consistency between experimental and simulation results is instructive for the practical forming process of railway spring fasteners

Exploring the use of graphene lubricant and TiO2 nanolubricants in micro deep drawing of stainless steel SUS301

This study investigates the effects of different lubrication conditions on drawing force and microcup formation during micro deep drawing (MDD). Results show that graphene lubricant, in combination with TiO2 nanolubricants, has the potential to reduce friction during MDD. The peak drawing force was reduced by 15.39% when both lubricants were used together, while the use of TiO2 nanolubricant and 10.0 mg/ml graphene lubricant reduced it by 6.03% and 14.52%, respectively. The study also reveals that lubricants reduce wrinkling during the formation of microcups by minimising energy consumption during the primary formation. However, the combination of TiO2 nanolubricant and graphene lubricant can cause inhomogeneous formation on the upper part of the blank, leading to more apparent wrinkling. Overall, the study highlights the potential of TiO2 nanolubricant and graphene lubricant in reducing friction and improving microcup formation during MDD.Open Access funding enabled and organized by CAUL and its Member Institutions. This research received funding from the Australian Research Council (ARC) through the project designated as DP190100738

Experimental and numerical study on micro deep drawing with aluminium-copper composite material

Micro forming is a promising technology with the trend towards miniaturisation in industry, and micro deep drawing (MMD) process is a fundamental micro forming method with potential applications in forming of cups, hollows and boxes and has great advantages comparing to other micro manufacturing methods. As the preferred material for electrical conductors, aluminium (Al)-copper (Cu) composite material processes advantages of the low density and cost of aluminium and good conductivity of copper. In this paper, MMD has been studied experimentally and numerically with a purpose of understanding the deformation behaviour of a two-layer Al-Cu composite in microscale. Al-Cu composite material was rolled to 50 µm in thickness and then annealed at 400 ºC. The drawability of the annealed composite was investigated by MDD experiments. FE models with Voronoi tessellations were established to simulate the Al-Cu composite material during MDD process. Considering the grain heterogeneity, each Voronoi tessellation has been assigned with different mechanical properties based on experimental data. The simulation results are in good agreement with the experiment ones

Micro forming of metallic composites

As the popularisation of electronical devices, the development of micro systems has attracted the attention of the researchers. Therefore, it is crucial to identify the effects of relevant parameters in micro forming process. This study mainly focuses on the impact of holding time in heat treatment process on the properties of Cu-Al-Cu laminate composite materials during micro deep drawing process. The results demonstrate that the Cu-Al-Cu laminate composite material that experiences 10-minute holding time can obtain better properties. Furthermore, a simulation model of the micro forming process is developed and the simulation results are compared with the experimental ones

Effects of micro flexible rolling and annealing on microstructure, microhardness and texture of aluminium alloy

The microstructure and texture after plastic deformation are strongly dependent on the corresponding manufacturing process and subsequent annealing which significantly affect the properties of the final products. In this study, 1060 aluminium alloy with a thickness of 464 μm was micro flexibly rolled to a constant thickness ratio of 3.6 by a combined control of the roll gap, the rolling speed and the roll lifting speed. Afterwards, the rolled specimens were subjected to isochronal annealing at a temperature range of 200 to 400 °C for 30 min and isothermal annealing at 400 °C for 10-60 min. Results indicate that the microstructure, microhardness and texture of each thickness zone are distinctly influenced by the rolling parameters and annealing conditions. Specimens annealed at 400 °C for 30 min result in a relatively steady hardness distribution along the transition zones. Typical β fibre texture is observed in the specimens suffered from annealing while S is predominant in both micro flexibly rolled and annealed specimens