Theory of single point incremental forming

https://home.kpn.nl/i.w.c.emmens/pdf/36.pdf

An overview of stabilizing deformation mechanisms in incremental sheet forming

The paper deals with the testing and modelling of metals response when subjected to sheet forming operations. The focus is both on the modelling of hardening behaviour and yield criteria and on the description of the sheet metal formability limits. Within this scope, the paper provides a critical review of the models available today for predicting the material behaviour at both industrial and scientific level, and the tests needed to identify the models’ material parameters. The most recent advances in the field are also presented and discussed with particular emphasis on the challenges the sheet metal forming community is now facing.

Testing and modelling of material behaviour and formability in sheet metal forming

Mechanics of fracture in single point incremental forming

A review on forming techniques for manufacturing lightweight complex—shaped aluminium panel components

In recent work, the present authors constructed a closed‐form analytical model that is capable of dealing with the fundamentals of single‐point incremental forming (SPIF) and explaining the experim...

Single‐point incremental forming and formability—failure diagrams

Formability limits by fracture in sheet metal forming

Knowledge of the physics behind the fracture of material at the transition between the inclined wall and the corner radius of the sheet is of great importance for understanding the fundamentals of single point incremental forming (SPIF). How the material fractures, what is the state of strain and stress in the small localized deformation zone and how these two subjects are brought together in order to explain the overall formability of SPIF in terms of ductile damage are still not well understood. However, they are of great importance for improving the robustness and enhancing the predictability of currently existing numerical models and for extending the scope of industrial applications of the process. This paper attempts to provide answers to these questions by means of a new theoretical model for rotational symmetric SPIF that was developed under membrane analysis with bi-directional in-plane contact friction forces.

Revisiting the fundamentals of single point incremental forming by means of membrane analysis

The last years saw the development of two different views on how failure develops in single-point incremental forming (SPIF). Today, researchers are split between those claiming that fracture is always preceded by necking and those considering that fracture occurs with suppression of necking. Each of these views is supported by convincing experimental and theoretical arguments that are available in the literature. This paper revisits failure in SPIF and presents a new level of understanding on the influence of process variables such as the tool radius that assists the authors to propose a new unified view on formability limits and development of fracture. The unified view conciliates the aforementioned different explanations on the role of necking in fracture and is consistent with the experimental observations that have been reported in the past years. The work is performed on aluminium AA1050-H111 sheets and involves independent determination of formability limits by necking and fracture using tensile and hydraulic bulge tests in conjunction with SPIF of benchmark shapes under laboratory conditions.

Maria Beatriz Silva

Papers

Theory of single point incremental forming

Single‐point incremental forming and formability—failure diagrams

Formability limits by fracture in sheet metal forming

Revisiting the fundamentals of single point incremental forming by means of membrane analysis

Failure mechanisms in single-point incremental forming of metals.