Progressive and Compound Forming for Producing Plunger-Typed Microparts by Using Sheet Metal

Abstract The plunger part in temporary electronic connectors is traditionally fabricated by micromachining. Progressive forming of microparts by directly using sheet metals is developed and proven to be an efficient microforming process to overcome some intrinsic drawback in realization of mass production of microparts. By employing this unique micromanufacturing process, an efficient approach with progressive microforming is developed to fabricate plunger-shaped microparts. In this endeavor, a progressive forming system for making microplungers using extrusion and blanking operations is developed, and the grain size effect affected deformation behaviors and of surface qualities of the microformed parts are studied. The knowledge for fabrication of plunger-shaped microparts via progressive microforming is developed, and the in-depth understanding and insight into the deformation behaviors and tailoring the product quality and properties will facilitate the design and development of the forming process by using this unique microforming approach.

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Grain Size Effect in Sheet Metal Microforming Simulation Adopting Strain Gradient Concept

Optics Design and Precision Manufacturing Technologies - Key Engineering Materials ◽

10.4028/0-87849-458-8.1285 ◽

2007 ◽

pp. 1285-1291

Author(s):

Wing Bun Lee ◽

Yi Ping Chen ◽

S. To

Keyword(s):

Grain Size ◽

Size Effect ◽

Sheet Metal ◽

Strain Gradient ◽

Grain Size Effect

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Grain size effect on tensile deformation behaviors of pure aluminum

Materials Science and Engineering A ◽

10.1016/j.msea.2021.141504 ◽

2021 ◽

pp. 141504

Author(s):

B.B. Wang ◽

G.M. Xie ◽

L.H. Wu ◽

P. Xue ◽

D.R. Ni ◽

...

Keyword(s):

Grain Size ◽

Size Effect ◽

Tensile Deformation ◽

Pure Aluminum ◽

Grain Size Effect ◽

Deformation Behaviors

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A Review of Progressive and Compound Forming of Bulk Microparts by Using Sheet Metals

MATEC Web of Conferences ◽

10.1051/matecconf/201819001001 ◽

2018 ◽

Vol 190 ◽

pp. 01001 ◽

Cited By ~ 2

Author(s):

M.W. Fu ◽

J.Y. Zheng ◽

B. Meng

Keyword(s):

Size Effect ◽

Sheet Metal ◽

Material Flow ◽

Dimensional Accuracy ◽

Promising Method ◽

Sheet Metals ◽

Forming Process ◽

Geometrical Feature

In the last decade, the concept of progressive microforming has emerged and developed gradually, which is considered as an efficient and promising method to fabricate the micro-scaled part. Micro-cylinder parts, micro-flanged part, and multi-flanged microparts are representative micro bulk parts by the progressive microforming system using sheet metal. In these cases, many efforts focus on the forming process, such as microblanking and microextrusion. Meanwhile, the quality of the fabricated parts also attracts attention. In this paper, an intensive review on the development of progressive microforming technologies and the formed parts is presented, and the influence of size effect to dimensional accuracy, material flow, geometrical feature, and fracture is also discussed.

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Grain Size Effect in Sheet Metal Microforming Simulation Adopting Strain Gradient Concept

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.364-366.1285 ◽

2007 ◽

Vol 364-366 ◽

pp. 1285-1291

Author(s):

Wing Bun Lee ◽

Yi Ping Chen ◽

Suet To

Keyword(s):

Grain Size ◽

Size Effect ◽

Sheet Metal ◽

Crystal Plasticity ◽

Strain Gradient ◽

Grain Size Effect ◽

Active System ◽

Rate Dependent ◽

Slip Resistance ◽

Non Local

A strain gradient dependent crystal plasticity approach is adopted to model the size effect in the microforming process of sheet metal. To take into account the grain size effect in the simulation, the total slip resistance in each active system was assumed to be due to a mixed population of forest obstacles arising from both statistically stored and geometrically necessary dislocations. The non-local crystal plasticity has been established by directly incorporating the above slip resistance into the conventional rate-dependent crystal plasticity and implemented into the Abaqus/Standard FE platform by developing the user subroutine UMAT. The formulation has been recapitulated and followed by presentation of the numerical examples employing both the local and non-local formulation. The comparison of the counterpart simulation results reveals the grain size effect in the microforming process and demonstrates the availability of the code developed.

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Grain Size Effect on Saddle Phenomenon in V-Bending Process of Thin Sheet Metal

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.773.202 ◽

2018 ◽

Vol 773 ◽

pp. 202-207

Author(s):

Chang Cheng Chen ◽

Yi Xiang Hong

Keyword(s):

Grain Size ◽

Size Effect ◽

Sheet Metal ◽

Design Method ◽

Tensile Force ◽

Thin Sheet ◽

Grain Size Effect ◽

Sheet Metal Parts ◽

Grain Sizes ◽

Thin Sheet Metal

The ability for predicting the springback on sheet metal bending processes is identified as an important feature of the ability for predicting the final geometry of sheet metal parts. The grain size effect makes the difficult on application of traditional design method in processing. As through tool and processing design, to understand the effects of grain size effects is an important and powerful way to effectively compensate for and eliminate the springback. In this paper, 99.5% pure iron specimens were annealed at different temperature to obtain the specified grain sizes. The effects of different grain sizes on the saddle after V-bending of the thin sheet metal were investigated. The results show that at the same thickness of specimens, the grain size has no significant effect on the saddle height. However, with increasing the thickness of the specimens the saddle will also be more prominent protruding height. The concave side of bent specimen is against the compression force and its grains structure tend to a round shape, whereas the convex side is against the tensile force and its grains structure tend to a flaky shape.

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Investigation of Electrically-Assisted Rolling Process of Corrugated Surface Microstructure with T2 Copper Foil

Materials ◽

10.3390/ma12244144 ◽

2019 ◽

Vol 12 (24) ◽

pp. 4144 ◽

Cited By ~ 5

Author(s):

Shaoxi Xue ◽

Chunju Wang ◽

Pengyu Chen ◽

Zhenhai Xu ◽

Lidong Cheng ◽

...

Keyword(s):

Grain Size ◽

Size Effect ◽

Copper Foil ◽

High Efficiency ◽

Grain Size Effect ◽

Electrical Parameters ◽

Forming Process ◽

Forming Quality ◽

Electrically Assisted

Electrically-assisted (EA) forming is a low-cost and high-efficiency method to enhance the formability of materials. In the study, EAF tensile tests are carried out to study the properties of T2 copper foil in an annealed state, and the effect of the electric current on the forming quality of corrugated foils is further studied in the EA rolling forming process. The result shows that the current reduces the flow stress and the fracture strain, which is different from the result of rolled samples. The joule heating effect on mechanical properties is significant in EA tension, and the softening effect of the surface layer can be observed at tensile strength, due to the grain size effect. Moreover, the current can weaken the grain size effect. In the rolling forming process, the influence of different electrical parameters on the forming height is remarkable, especially for the rolled T2 copper. The appropriate electrical parameters can improve the forming height, while keeping a small thickness thinning. Nevertheless, the high current density will lead to local rupture. This study proves that the current can improve the forming quality of the corrugated foils and is a promising surface texture forming process.

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The Effects of Grain Size and Lubrication on Micro Curl Forming Process of Metallic Thin Sheet

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.661.55 ◽

2015 ◽

Vol 661 ◽

pp. 55-61

Author(s):

Chang Cheng Chen ◽

Huey Lin Ho

Keyword(s):

Mechanical Properties ◽

Grain Size ◽

Size Effect ◽

Deformation Behavior ◽

Thin Sheet ◽

Grain Size Effect ◽

Forming Process ◽

Grain Sizes ◽

Different Temperatures ◽

Different Thickness

This article aims at the discussion of deformation behavior considering size effect on curl forming process of sheet metal. In this study, the test specimens were made by phosphor bronze sheets for curl forming test. The specimens with different thickness were firstly heated at different temperatures for obtaining the objective grain sizes. And the mechanical properties of specimen were acquired by using tensile test. Through the curl forming test with a curl forming machine, the curled angles, springback and curling load were measured and analyzed for investigating the grain size effect of the chamfer and carbon lubricant during the curl forming process.

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