Effect of post-weld aging on the mechanical and microstructural properties of friction stir welded aluminum alloy 7075

• Autorzy: Yeni C. , Sayer S. , Ertugrul O. , Pakdil M.
• Języki publikacji: EN

Abstrakty

EN

Purpose: of this paper is to investigate the effect of post-weld artificial aging on the friction stir welding of Aluminum Alloy 7075 (AA 7075) for a welding condition of 1600 rpm and 100 mm/min using right and left helical screwed pins for two different shoulder diameters. Design/methodology/approach: The method followed is that first artificial aging has been carried out as 24 hours at 125°C. Afterwards, in order to study the effect of post-weld aging on tool geometry, microstructural examination, hardness measurements and room temperature tensile tests have been carried out. Findings: The results show that left helical screw yields higher mechanical properties and hardness values compared to right helical screw when tested at the same shoulder diameter. It has been observed that post weld aging process compensates the hardness decrease observed in as-welded joints; no significant decrease in hardness is obtained throughout the weld region. Research limitations/implications: For future work it can be suggested to vary the post weld aging condition, such as 12 hours at 125°C. Welding and rotation speeds are other parameters affecting the microstructural and mechanical properties; therefore the effect of varying these parameters should be considered. Practical implications: This study has practical implications and direct applicability. It indicates that helix angle rather than shoulder diameter directly affects the quality of the joint. At certain post weld aging conditions, for obtaining a sound welded joint the right tool selection will be of critical importance. Originality/value: The authors have examined the effect of post weld aging for different helix angles and shoulder diameters. It is believed that examination of the effect of the variation of these parameters on the joint quality provides originality to this study.

Słowa kluczowe

EN

mechanical properties; post weld aging; AA7075; microstructure; friction stir welding

PL

właściwości mechaniczne; starzenie po spawaniu; stop aluminium 7075; mikrostruktura; technologia zgrzewania FSW

• Wydawca: International OCSCO World Press
• Czasopismo: Archives of Materials Science and Engineering
• Rocznik: 2008
• Tom: Vol. 34, nr 2
• Strony: 105--109
• Opis fizyczny: Bibliogr. 12 poz.

Twórcy

autor

Yeni C.

autor

Sayer S.

autor

Ertugrul O.

autor

Pakdil M.

• Department of Mechanical Engineering, Faculty of Engineering, Dokuz Eylul University, Bornova-Ýzmir, Turkey,

Bibliografia

• [1] C.G. Rhodes, M.W. Mahoney, W.H. Bingel, Effects of friction stir welding on microstructure of 7075 Aluminum, Scripta Materialia 36/1 (1997) 69-75.
• [2] R.S. Mishra, Z.Y. Ma, S.R. Sharma, M.W. Manohey, Microstructural modification of cast Aluminum alloys via friction stir processing, Materials Science Forum 426-432 (2003) 2891-2896.
• [3] S. Sayer, V. Ceyhun, Influence of pin structure on microstructure and mechanical properties of friction stir welded 6063 (Almgsi0.5) Aluminum alloy, Materials Testing 50/5 (2008) 259-263.
• [4] C. Zhou, X. Yang, G. Luan, Investigation of microstructures and fatigue properties of friction stir welded Al-Mg alloy, Materials Chemistry and Physics 98 (2006) 285-290.
• [5] W. Tang, X. Guo, J.C. McClure, L.E. Murr, Heat input and temperature distribution in friction stir welding, Journal of Materials Processing and Manufacturing Science 7 (1998) 163-172.
• [6] C. Zhou, X. Yang, G. Luan, Fatigue properties of friction stir welds in Al 5083 alloy, Scripta Materialia 53 (2005) 1187-1191.
• [7] M. Czechowski, Low cycle fatigue of friction stir welded Al-Mg alloys, Journal of Materials Processing Technology 164-165 (2005) 1001-1006.
• [8] Ç. Yeni, The effect of welding parameters on the microstructure and mechanical properties of friction stir welded AA 7075, Practical Metallurgy 45/10 (2008) 479-494.
• [9] G. Liu, L.E Murr, C-S. Niou, J.C. McClure, F.R. Vega, Microstructural aspects of the friction-stir welding of 6061- T6 Aluminum, Scripta Materialia 37/3 (1997) 355-361.
• [10] R.S. Mishra, Z.Y. Ma, Friction stir welding and processing, Materials Science and Engineering 50 (2005) 1-78.
• [11] Z.Y. Ma, R.S. Mishra, M.W. Mahoney, Superplastic deformation behavior of friction stir processed 7075 Al Alloy, Acta Materialia 50/17 (2002) 4410-4430.
• [12] Y.S. Sato, H. Kokawa, M. Enmoto, S. Jogan, Microstructural evaluation of 6063 Aluminum during friction-stir welding, Metallurgical and Materials Transactions A 30/9 (1999) 2429-286.