Effect of forming rate on the impact tensile properties of the steels under crash test

• Autorzy: Bayraktar E. , Grumbach M. , Kaplan D.
• Konferencja: 12th International Scientific Conference CAM3S'2006, 27-30th November 2006, Gliwice-Zakopane
• Języki publikacji: EN

Abstrakty

EN

Purpose: The main objective of this study is to examine the mechanical and metallurgical behaviour of the tailored blanks and base metals for thin sheet steels used in the car industry by using a new type of crash test/ impact (ITT). It exposes the effect of forming rate on the toughness of thin welded joints (tailored blanks) for Interstitial Free (IFS) steels used in the automotive industry. Design/methodology/approach: A special crash test device is used in different temperature and the simulated crash tests are performed at a constant speed of 5.52 m/s (strain rate about 250 s to the -1). Findings: The specimen is submitted to impact tensile test at different temperatures. According to testing temperature, fracture mode varies: At low temperatures, brittle fracture occurs: Due to stress concentration, fracture always occurs in the notched section. At high temperatures, the specimen fails by ductile fracture. Toughness of the steel sheets (base metals, BM or tailored blanks, TBs) after forming at certain levels is well compared at different materials and test conditions. Practical implications: This study gives very useful data for the crash test. This is a new conception of specimen and of the impact/crash machine. It is easily used in automotive industry for practical and economic reason to give rapid answers to designer and also steel makers for ranking the materials. Originality/value: This research used a new developed test called simlified crash test for evaluating the effect of forming rate on the toughness of thin welded joints (tailored blanks) / mechanical assemblies in high formability steel sheets for stamping submitted to dynamic loads such as experienced in real crash tests.

Słowa kluczowe

EN

mechanical properties; crash test; tailored blanks; forming; interstitial free steel; interstitial free - IF

PL

właściwości mechaniczne; testy zderzeniowe; półfabrykaty do tłoczenia; kształtowanie; stal bez pierwiastków międzywęzłowych

• Wydawca: International OCSCO World Press
• Czasopismo: Journal of Achievements in Materials and Manufacturing Engineering
• Rocznik: 2007
• Tom: Vol. 20, nr 1-2
• Strony: 55--60
• Opis fizyczny: Bibliogr. 18 poz., fot., rys.

Twórcy

autor

Bayraktar E.

autor

Grumbach M.

autor

Kaplan D.

• Supmeca/LISMMA-Paris, School of Mechanical and Manufacturing Engineering, EA 2336, St-Ouen, France,

Bibliografia

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