Effect of Pb on Microstructure and Mechanical Properties of AZ91 Magnesium Alloy

Subject Areas : journal of New Materials

Mohammad Reza Askaran ¹ , Masoud Emamy ² , Mehdi Malekan ³

1 - MSc student, School of Metallurgy and Materials Engineering, College of Engineering, University of Tehran, Tehran
2 - School of Metallurgy and Materials Engineering, College of Engineering, University of Tehran, Tehran, Iran
3 - School of Metallurgy and Materials Engineering, College of Engineering, University of Tehran, P.O. Box 14395-515, Tehran, Iran

Received: 2017-07-31 Accepted : 2018-10-07 Published : 2018-09-23

Keywords: Microstructure, mechanical properties, Grain size, AZ91 magnesium alloy, Lead (Pb),

Abstract :

In this study, the effect of different amounts of Pb (0, 0.5, 1, 3 wt.%) was investigated on the microstructure and mechanical properties of the AZ91 magnesium alloy. The microstructure and mechanical properties were Studied using optical microscope, scanning electron microscope (SEM), X-ray diffractometer (XRD) and tensile test. The results showed that by adding Pb, the volume fraction of the β- Mg17Al12 phase decreased. It was also found that the grain size by 1 wt.% Pb addition decreased significantly and the formation tendency of the divorced eutectic phase reduced. Furthermore, the optimum amount of UTS and elongation were observed by the addition of 1 wt.% Pb to AZ91 magnesium alloy. UTS and elongation increased from 129 MPa and 2.7% to 160 MPa and 7%, respectively, when the 1 wt.% Pb was added to the AZ91 alloy. The fracture surface observations showed that the fracture mode in these alloys were cleavage and the Pb addition does not change the fracture mode.

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AZ 36 بررسی تاثیر سرب بر ریز ساختار و خواص مکانیکی آلیاژ منیزیم 91

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