Search results for "Formability"

Association of erythrocyte deformability with red blood cell distribution width in metabolic diseases and thalassemia trait.

2016

Abstract Increased red blood distribution width (RDW) in anemia is related to disturbances in the cellular surface/volume ratio, usually accompanied by morphological alterations, while it has been shown in inflammatory diseases that the activity of pro-inflammatory cytokines disturbing erythropoiesis increases RDW. Recently it has been reported that higher RDW is related with decreased erythrocyte deformability, and that it could be related with the association of RDW and increased risk of cardiovascular diseases. In order to analyze the influence of morphological alterations and proinflammatory status on the relationship between RDW and erythrocyte deformability, we analyzed erythrocyte de…

Enhancing formability of aluminium alloys by superimposing hydrostatic pressure

2003

Publisher Summary One of the strategic topics in manufacturing engineering is represented by the reduction of components weight. This aim is pursued by utilizing accurate and effective design tools and using lightweight metals such as aluminum, magnesium, and titanium alloys. Unfortunately, such materials often show a poor ductility, and thus enhancing formability is nowadays one of the most relevant research focus, as well as the development of effective and reliable predictive models of defects insurgence during forming processes. In this scenario, forming by means of superimposed hydrostatic pressure represents a promising alternative manufacturing technique. The chapter discusses the si…

Shape distortion and thickness distribution during SPIF processes: experimental and numerical analysis

2011

Single Point Incremental Forming (SPIF) is a quite new sheet forming process which offers the possibility to deform complex parts without dedicated dies using only a single point tool and a standard 3-axis CNC machine. The process mechanics enables strains much higher than traditional sheet forming processes, but particular attention must be given to the final part geometrical accuracy. In this paper the capabilities of a dedicated explicit numerical model are quantitatively analyzed on pyramid-shaped parts. In particular a comparison between experimental and numerical results is reported. Three different shapes at the varying of the stamping angle were considered and the final shape was ac…

Formability of friction stir welding AZ31 magnesium alloy sheets

2010

Influence of mechanical properties of the sheet material on formability in single point incremental forming

2004

Abstract New trends in sheet metal forming are rapidly developing and several new forming processes have been proposed to accomplish the goals of flexibility and cost reduction. Among them single point incremental forming operations, in which the final shape of the component is obtained by the relative movement of a simple and small punch with respect to the blank, appear quite promising. In the paper, material formability issues in incremental forming were studied. Some relevant correlations among material formability and other mechanical properties of the material were analysed. The FLD 0 value, i.e. the major strain at fracture in plane strain conditions, was determined for different mat…

Analysis of Some Innovative and Flexible Sheet Forming Processes

2002

In the field of sheet forming, innovative and flexible processes that do not impose the use of expensive conventional equipments and/or do not require time consuming set-up operations have become, nowadays, a rather promising research topic. Two different main lines are currently followed: the former is based on the development of new stamping processes based on the utilization of flexible media, while the latter is aimed to develop so called progressive forming processes (spinning and incremental forming). Both hydro-forming and incremental forming permit a very relevant reduction of the tooling and set-up costs and improve process flexibility. These items are discussed in detail in the pa…

Robot-based incremental sheet forming – the tool path planning

2021

Abstract To achieve a 3D shape with certain degree of complexity from metal sheets that are flat in the beginning, especially for prototype development or small series production, that is also cost efficient by avoiding high-end dies or expensive tooling, the incremental sheet forming process can represent the ideal choice due to its flexibility, reduced forming forces and increased formability. The process is performed with a round tool that follows a predefined path to deform the flat metal sheet into its final shape. The proper selection of the toolpaths affects the productivity and the accuracy of each part. The process having to focus on forming each single point in increments. For cos…

Process mechanics analysis in single point incremental forming

2004

The request of highly differentiated products and the need of process flexibility have brought the researchers to focus the attention on innovative sheet forming processes. Industrial application of conventional processes is, in fact, economically convenient just for large scale productions; furthermore conventional processes do not allow to fully satisfy the mentioned demand of flexibility. In this contest, single point incremental forming (SPIF) is an innovative and flexible answer to market requests. The process is characterized by a peculiar process mechanics, being the sheet plastically deformed only through a localised stretching mechanism. Some recent experimental studies have shown …

Incremental forming of friction stir welded taylored sheets

2006

In the last decade sheet metal forming market has undergone substantial mutations since the development of more efficient strategies in terms of flexibility and cost reduction is strictly due. Such requirements are not consistent with traditional metal stamping processes which are characterized by complex equipment, capital and tooling costs; thus the industrial application of such processes is economically convenient just for large scale productions. For this reason most of the research work developed in the last years has been focused on the development of new sheet forming processes able to achieve the above discussed goals. Contemporary, with particular reference to the automotive indus…

A numerical approach for the modelling of forming limits in hot incremental forming of AZ31 magnesium alloy

2021

AbstractMagnesium alloys, because of their good specific material strength, can be considered attractive by different industry fields, as the aerospace and the automotive one. However, their use is limited by the poor formability at room temperature. In this research, a numerical approach is proposed in order to determine an analytical expression of material formability in hot incremental forming processes. The numerical model was developed using the commercial software ABAQUS/Explicit. The Johnson-Cook material model was used, and the model was validated through experimental measurements carried out using the ARAMIS system. Different geometries were considered with temperature varying in a…