Prediction of Forming Limit in Single Point Incremental Forming With the Ductile Fracture Criterion

2007 ◽  
Author(s):  
Y. Huang ◽  
Y. J. Wang ◽  
J. Cao ◽  
M. Li
Keyword(s):  
Ductile Fracture ◽  
Fracture Criterion ◽  
Incremental Forming ◽  
Single Point ◽  
Forming Limit Diagram ◽  
Theoretical Work ◽  
Negative Slope ◽  
Forming Limit ◽  
Single Point Incremental Forming ◽  
Ductile Fracture Criterion

Many experiments have been conducted to investigate the forming limit in single point incremental forming (SPIF). The forming limit curve (FLC) generated from these experiments follows a linear line with a negative slope in the positive minor strain side of the forming limit diagram (FLD). It is also found that, in general, for the same material subjected to the SPIF process, the failure strain level greatly exceeds the traditional FLC based on theories of the plastic instability [Iseki and Kumon, 1994]. Currently, no theoretical work or no criterion was proposed to predict this FLC in the SPIF. In this paper, the criterion for the ductile fracture [Oyane, 1980] is introduced to try to predict the forming limit of the material in the SPIF. Based on the calculated stress and strain from the finite element simulation and the ductile fracture criterion, the fracture initiation site and the forming limit are predicted. The predicted results are compared with that from the SPIF experiment to verify the feasibility of the proposed method.

Prediction and Research of Single Point Incremental Forming Limit

2010 ◽  
Vol 97-101 ◽  
pp. 4005-4009
Author(s):  
Lei Li ◽  
Wan Lin Zhou ◽  
Ghulam Hussain
Keyword(s):  
Fracture Criterion ◽  
Incremental Forming ◽  
Single Point ◽  
Fracture Initiation ◽  
Forming Limit ◽  
Ductile Fracture Criterion ◽  
Limit Curve ◽  
Forming Limit Curve ◽  
Strain Data ◽  
Characteristic Stress

Sing point incremental forming (SPIF) limit is much higher than the traditional processes. Currently, there are still no systematic theories and criterions to predict the limit. In this paper, the Oyane ductile fracture criterion is introduced to predict the forming limit of SPIF based on the stress-strain data by the finite element simulations. The predicted fracture initiation sites and the forming limit curve are consistent with the experiment results; further, the forming characteristic, stress state, local temperature are the main reasons of the higher forming limit in SPIF.

scholarly journals Forming Limit Research of 5182 Aluminum Alloy Sheet Based on Lou-2013 Ductile Fracture Criterion

2019 ◽  
Vol 55 (16) ◽  
pp. 47 ◽  
Author(s):  
YANG Zhuoyun ◽  
ZHAO Changcai ◽  
DONG Guojiang ◽  
CHEN Guang ◽  
ZHU Liangjin ◽  
...  
Keyword(s):  
Aluminum Alloy ◽  
Ductile Fracture ◽  
Fracture Criterion ◽  
Alloy Sheet ◽  
Forming Limit ◽  
Aluminum Alloy Sheet ◽  
Ductile Fracture Criterion

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.

Sign in / Sign up

Export Citation Format

Share Document