Investigation of The Effect of Notch Tip Radius on Fracture Energy of Charpy in 7075 Aluminium Alloy

ADMT Journal

مقاله 7، دوره 13، شماره 2، شهریور 2020، صفحه 65-72   

نوع مقاله: Original Article

نویسندگان

Ali Hossein zadeh^{* 1}؛ Mohammad Reza Maraki²؛ Mohsen Sadidi³

¹Department of Mechanical Engineering, Ferdowsi University of Mashhad, Iran

²Department of Material Engineering, Birjand University of Technology, Birjand, Iran

³Department of Civil Engineering, Shahrood University of Technology, Iran

چکیده

In the present study Charpy impact tests on a 7075-T651 aluminium alloy with full size (55×10×10 mm) with different notch tip radius (range of 0.19 to 0.40 mm) were conducted and the fracture energy was measured. The experimental results showed that the relationship between the fracture energy (E) and the notch tip radius of the Charpy samples (r) for the tested Aluminium is E=18.052r+1.741. Using this relationship, the Charpy energy can be determined for this Aluminium for any notch tip radius. Fracture surfaces revealed an intergranular failure for base metal in longitudinal direction, that a predominately brittle failure (cleavage) with some insights of ductile characteristics was observed. Moreover, with increasing notch tip radius, cracked particles were observed and some microvoids were nucleated, i.e., ductile fracture. Changes in the primary crack notch cause a change in the stress intensity factor adjacent to the crack tip, where the fracture energy in the Charpy Impact Test is subjected to the primary crack notch.

کلیدواژه‌ها

Aluminum Alloy 7075؛ Charpy Impact Test؛ Notch Tip Radius Effect؛ V-Notch

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