Single point incremental forming of a facial implant

2013 ◽  
Vol 38 (5) ◽  
pp. 369-378 ◽  
Author(s):  
Rogério Araújo ◽  
Pedro Teixeira ◽  
Luciana Montanari ◽  
Ana Reis ◽  
Maria B Silva ◽  
...  
Keyword(s):  
Graphical Representation ◽  
Incremental Forming ◽  
Low Cost ◽  
Single Point ◽  
Manufacturing Technology ◽  
Medical Community ◽  
Patient Specific ◽  
Forming Limit ◽  
Single Point Incremental Forming ◽  
Medical Implants

Background: The investigation draws from the fundamentals of the mechanical behaviour of titanium grade 2 to the design and fabrication of facial implants by means of single point incremental forming. Objectives: To provide knowledge on the capabilities and limitations of a new manufacturing technology to fabricate low-cost, patient-specific medical implants. Study design: Rapid fabrication of a simplified model of a facial implant. Methods: Circle grid analysis and its graphical representation in the fracture forming limit diagram combined with finite element modelling are utilized to identify the failure limits and to assist the overall design of the facial implants. Results: Fabrication of facial implants without and with failure by cracking due to excessive thinning of the sheet from where the implant is to be cut. Conclusions: Identification of the major operative parameters that influence fabrication of sound facial implants by means of single point incremental forming. Clinical relevance Reduce the gap between production engineers and the medical community by presenting a state-of-the-art manufacturing technology to produce low-cost, patient-specific medical implants.

Study on Forming Behaviour of Friction Stir Welded Blanks During Single Point Incremental Forming (SPIF) Process

2020 ◽  
Author(s):  
Shalin Marathe ◽  
Harit Raval
Keyword(s):  
Friction Stir Welding ◽  
Incremental Forming ◽  
Single Point ◽  
Base Material ◽  
Forming Limit ◽  
Single Point Incremental Forming ◽  
Cnc Milling ◽  
Forming Process ◽  
Friction Stir ◽  
Welding Processes

Abstract The automobile, transportation and shipbuilding industries are aiming at fuel efficient products. In order to enhance the fuel efficiency, the overall weight of the product should be brought down. This requirement has increased the use of material like aluminium and its alloys. But, it is difficult to weld aluminium using conventional welding processes. This problem can be solved by inventions like friction stir welding (FSW) process. During fabrication of product, FSW joints are subjected to many different processes and forming is one of them. During conventional forming, the formability of the welded blanks is found to be lower than the formability of the parent blank involved in it. One of the major reasons for reduction in formability is the global deformation provided on the blank during forming process. In order to improve the formability of homogeneous blanks, Single Point Incremental Forming (SPIF) is found to be giving excellent results. So, in this work formability of the welded blanks is investigated during the SPIF process. Friction Stir Welding is used to fabricate the welded blanks using AA 6061 T6 as base material. Welded blanks are formed in to truncated cone through SPIF process. CNC milling machine is used as SPIF machine tool to perform the experimental work. In order to avoid direct contact between weld seam and forming tool, a dummy sheet was used between them. As responses forming limit curve (FLC), surface roughness, and thinning are investigated. It was found that use of dummy sheet leads to improve the surface finish of the formed blank. The formability of the blank was found less in comparison to the parent metal involved in it. Uneven distribution of mechanical properties in the welded blanks leads to decrease the formability of the welded blanks.

Experimental Study on Residual Formability of Single Point Incrementally Formed Part

2019 ◽  
Author(s):  
Chetan P. Nikhare
Keyword(s):  
Sheet Metal ◽  
Sheet Metal Forming ◽  
Metal Forming ◽  
Incremental Forming ◽  
Thickness Distribution ◽  
Single Point ◽  
Forming Limit ◽  
Single Point Incremental Forming ◽  
Forming Process ◽  
Conventional Process

Abstract A substantial increase in demand on the sheet metal part usage in aerospace and automotive industries is due to the increase in the sale of these products to ease the transportation. However, due to the increase in fuel prices and further environmental regulation had left no choice but to manufacture more fuel efficient and inexpensive vehicles. These heavy demands force researchers to think outside the box. Many innovative research projects came to replace the conventional sheet metal forming of which single point incremental forming is one of them. SPIF is the emerging die-less sheet metal forming process in which the single point tool incrementally forces any single point of sheet metal at any processing time to undergo plastic deformation. It has several advantages over the conventional process like high process flexibility, elimination of die, complex shape and better formability. Previous literature provides enormous research on formability of metal during this process, process with various metals and hybrid metals, the influence of various process parameter, but residual formability after this process is untouched. Thus, the aim of this paper is to investigate the residual formability of the formed parts using single point incremental forming and then restrike with a conventional tool. The common process parameters of single point incremental forming were varied, and residual formability was studied through the conventional process. The strain and thickness distribution were measured and analyzed. In addition, the forming limit of the part was plotted and compared.

Assessing 3 and 5 Degrees of Freedom Toolpath Strategy Influence on Single Point Incremental Forming

2015 ◽  
Vol 651-653 ◽  
pp. 1159-1162 ◽  
Author(s):  
João B. Sá de Farias ◽  
Ricardo P. Bastos ◽  
Jorge A. Ferreira ◽  
Ricardo J. Alves de Sousa
Keyword(s):  
High Strength Steel ◽  
Degrees Of Freedom ◽  
Incremental Forming ◽  
Single Point ◽  
High Strength ◽  
Manufacturing Technology ◽  
Single Point Incremental Forming ◽  
Payload Capacity ◽  
The University ◽  
High Payload

Single Point Incremental Forming (SPIF) is a promising manufacturing technology concerning the production of customized products, low batches or prototyping of ready-to-use parts, given its easy implementation and absence of dedicated tooling. The range of application is wide, covering many materials and virtually unlimited geometries. Indeed, nowadays’ boundaries of the process are more related to the machines limitations than to the process itself. The SPIFA machine [1] developed at the University of Aveiro allies high payload capacity to flexibility driven by a kinematics based on a Stewart Platform. In this work, it will discussed the effects of employing five degrees of freedom toolpaths to produce aluminium and high strength steel parts.

scholarly journals Influences of Vibration Parameters on Formability of 1060 Aluminum Sheet Processed by Ultrasonic Vibration-Assisted Single Point Incremental Forming

2019 ◽  
Vol 2019 ◽  
pp. 1-12
Author(s):  
Mingshun Yang ◽  
Lang Bai ◽  
Yan Li ◽  
Qilong Yuan
Keyword(s):  
Ultrasonic Vibration ◽  
Incremental Forming ◽  
Single Point ◽  
Aluminum Sheet ◽  
Forming Limit ◽  
Single Point Incremental Forming ◽  
Experimental Platform ◽  
Formed Part ◽  
Vibration Parameters ◽  
Forming Angle

With increasing design complexities of thin-walled parts, the requirement of enhanced formability has impeded the development of the single point incremental forming (SPIF) process. In the present research, the ultrasonic vibration-assisted single point incremental forming (UV-SPIF) method was introduced to increase the formability of sheet metals. AL1060 aluminum alloy was adopted as the experimental material, and a truncated cone part was considered as the research object. The simulation model of UV-SPIF was established to analyze the distribution of plastic strains in the formed part. A forming angle was selected as the measuring index of formability of the aluminum sheet, and the influences of different vibration parameters on formability were evaluated. An experimental platform was devised to verify the accuracy of the obtained simulation results. It was found that ultrasonic vibration effectively improved the forming limit of the sheet. When the amplitude was 6 µm and the frequency was 25 kHz, the sheet yielded the best formability with the largest forming angle of 67 degrees.

Revisiting single-point incremental forming and formability/failure diagrams by means of finite elements and experimentation

2009 ◽  
Vol 44 (4) ◽  
pp. 221-234 ◽  
Author(s):  
M B Silva ◽  
M Skjoedt ◽  
N Bay ◽  
P A F Martins
Keyword(s):  
Finite Element ◽  
Damage Mechanics ◽  
Incremental Forming ◽  
Single Point ◽  
Analytical Framework ◽  
Forming Limit ◽  
Single Point Incremental Forming ◽  
Forming Limits ◽  
Experimental Values ◽  
Forming Limit Curves

In a previously published work, the current authors presented an analytical framework, built upon the combined utilization of membrane analysis and ductile damage mechanics, that is capable of modelling the fundamentals of single-point incremental forming (SPIF) of metallic sheets. The analytical framework accounts for the influence of major process parameters and their mutual interaction to be studied both qualitatively and quantitatively. It enables the conclusion to be drawn that the probable mode of material failure in SPIF is consistent with stretching, rather than shearing being the governing mode of deformation. The study of the morphology of the cracks combined with the experimentally observed suppression of neck formation enabled the authors to conclude that traditional forming limit curves are inapplicable for describing failure. Instead, fracture forming limit curves should be employed to evaluate the overall formability of the process. The aim of this paper is twofold: (a) to compare the mechanics of deformation of SPIF, namely the distribution of stresses and strains derived from the analytical framework with numerical estimates provided by finite element modelling; and (b) to compare the forming limits determined by the analytical framework with experimental values. It is shown that agreement between analytical, finite element, and experimental results is good, implying that the previously proposed analytical framework can be utilized to explain the mechanics of deformation and the forming limits of SPIF.

Single Point Incremental Forming of a Medical Implant

2013 ◽  
Vol 554-557 ◽  
pp. 1388-1393 ◽  
Author(s):  
Rogério Araújo ◽  
Pedro Teixeira ◽  
M. Beatriz Silva ◽  
Ana Reis ◽  
Paulo Martins
Keyword(s):  
Plastic Deformation ◽  
Incremental Forming ◽  
Single Point ◽  
Sheet Forming ◽  
Incremental Sheet Forming ◽  
Potential Fields ◽  
Single Point Incremental Forming ◽  
Medical Implants ◽  
Medical Implant ◽  
Product Customization

Single point incremental forming (SPIF) belongs to the branch of incremental sheet forming processes that enables plastic deformation of blanks without resorting to any specific die or punch. The main characteristics of SPIF determine its appropriateness for producing small batches or single products, being the medical implants one of the key potential fields of application, due to the need of product customization to each patient. Customization is particularly important for obtaining preoperative implants because it allows a significant decrease in the overall surgery time in conjunction with a higher level of flexibility to ensure the required shapes. This results in an improved final product either in aesthetic as well as in functional terms.

Comparison of Predicted Forming Limit Curves with Measured Experimental Data on Hot-Dip Zinc-Coated Cold-Rolled Steel by Incremental Forming Process

2019 ◽  
Vol 821 ◽  
pp. 256-262 ◽  
Author(s):  
Ramil Kesvarakul ◽  
Khompee Limpadapun
Keyword(s):  
Experimental Data ◽  
Incremental Forming ◽  
True Strain ◽  
Single Point ◽  
Forming Limit ◽  
Rolled Sheet ◽  
Single Point Incremental Forming ◽  
Forming Process ◽  
Cold Rolled ◽  
Forming Limit Curves

Single Point Incremental Forming (SPIF) is a die-less forming process with advantages of high-flexibility, low-cost and short lead time. The high local strains that are applied to the metal sheet, often exceeding the conventional formability limit. This paper is focused on comparison of predicted forming limit curves with measured experimental data on Hot-Dip Zinc-Coated Cold-Rolled sheet, with 0.20 mm thick is studied in single point incremental forming. Truncated square pyramid and cone are formed to study the formability of blank sheets at room temperature. It was found that both Formulation of plastic instability criteria and Keeler’s formula gives the lowest FLC. FLDs have predicted failures in forming process consistently with the real experiments. The experimentally obtained cracking limit differ from analytical one and empirical one by about 3.398 and 2.135 true strain respectively at FLD0, the corresponding plane strain values.

Formability of AA7075 Sheet in Single Point Incremental Forming

2021 ◽  
Vol 11 (2) ◽  
pp. 40-54
Author(s):  
Gautam Kumar ◽  
Kuntal Maji
Keyword(s):  
Plane Strain ◽  
Strain Path ◽  
Incremental Forming ◽  
Single Point ◽  
Forming Limit ◽  
Single Point Incremental Forming ◽  
Wall Angle ◽  
Groove Test ◽  
Deformation Instability ◽  
Experimental Values

This article presents formability analysis of aluminium alloy 7075 thin sheets in single point incremental forming (SPIF) through prediction of forming limit curve (FLC) and maximum formable wall angle. Deformation instability method based on tool-sheet contact and non-contact zones in incremental forming was used for the prediction of limit strains for plane strain and equi-biaxial stretching strain path. FLC of the material was also determined experimentally, after measuring limit strains for deformed sheet through groove test for the process. Further, maximum forming wall angle of the material was determined for deformed sheet in a square pyramid shape. The theoretical limit strains predicted by deformation instability approach were compared to the experimental values. Theoretically, calculated limit strains were observed to be higher for plane strain path but approximately close for equi-biaxial strain path compared to experimental limit strains. The maximum formable wall was found to be 55˚ for the material in the process.

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