On the Determination of Flow Stress Using Bulge Test and Mechanical Measurement

• Type: Article in International Conference Proceedings Book
• Date: 2010

Authors

Abel D Santos (Author) FEUP; Pedro Teixeira (Author) FEUP; Barata da Rocha, A (Author) FEUP; Barlat, F (Author) Other; Barlat, F (Author) Other; Moon, YH (Author) Other; Lee, MG (Author) Other

Conference proceedings International

Title: NUMIFORM 2010, VOLS 1 AND 2: DEDICATED TO PROFESSOR O. C. ZIENKIEWICZ (1921-2009)

Pages: 845-852

10th International Conference on Numerical Methods in Industrial Forming Processes (NUMIFORM 2010)

Pohang, SOUTH KOREA, JUN 13-17, 2010

Indexing

ISI Web of Knowledge - 9 Citations

Scopus - 24 Citations

Scientific classification

FOS: Engineering and technology > Mechanical engineering

Other information

Authenticus ID: P-003-C69

DOI: 10.1063/1.3457644

Abstract (EN): The standard uniaxial tensile test is a widely accepted method to obtain relevant properties of sheet metal materials. These fundamental parameters can be used in numerical modeling of sheet forming operations to predict and assess formability and failure analysis. However the range of strain obtained from tensile test is limited and therefore if one will need further information on material behavior, extrapolation of tensile data is performed. The bulge test is an alternative to obtain ranges of deformation higher than tensile test, thus being possible to obtain non-extrapolated data for material behavior. Several methods may be used to obtain stress-strain data from bulge test, but a common concept is behind them, which needs the measurement of bulge pressure, curvature of bulge specimen, its thickness at the pole and the application of membrane theory. Concerning such measurements, optical methods are being used recently but classical mechanical methods are still an alternative with its own strengths. This paper presents the use and development of a mechanical measuring system to be incorporated in a hydraulic bulge test for flow curve determination, which permits real-time data acquisition under controlled strain rates up to high levels of plastic deformation. Numerical simulations of bulge test using FEM are performed and a sensitivity analysis is done for some influencing variables used in measurements, thus giving some directions in the design and use of the experimental mechanical system. Also, first experimental results are presented, showing an efficient testing procedure method for real time data acquisition with a stable evaluation of the flow curve.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 8