Enhancing the Hardness of Mg-9Al-1Zn Cast Alloy by Solution Treatment

International Conference on Condensed Matters and Advanced Materials 2018

Putra, Adi Ganda^1^2 ; Manaf, Azwar^1 ; Anawati, Anawati^1

Department of Physics, Faculty of Mathematics and Natural Sciences, Universitas Indonesia Depok, 16424, Indonesia^1

Mechanical Engineering, Faculty of Engineering, Universitas Jenderal Achmad Yani, Bandung

40285, Indonesia^2

关键词: Automotive component;    Hardness values;    Lightweight materials;    Magnesium metal;    Microstructure development;    Microstructure observation;    Processing method;    Solution treatments;   

Others  :  https://iopscience.iop.org/article/10.1088/1757-899X/515/1/012088/pdf
DOI  :  10.1088/1757-899X/515/1/012088

来源: IOP

【 摘 要 】

Magnesium alloys are lightweight materials that have a great potential to be developed because the alloy can reduce the energy consumption and total weight. The alloy is made of magnesium metal as a primary component characterized by a soft and mechanically low-strength. The addition of aluminium in Mg-Al system will form Mg17Al12 particles causing grain refining the effect of the α-Mg matrix. Similarly, the addition of Zn in Mg-Zn system increases the strength and hardness of the alloy. Hence, the combined addition of Al and Zn in Mg-Al-Zn system would be interesting for automotive component applications. In this study, we have carried out the casting process for Mg-9Al-1Zn (wt. %) through a gravity of the metal mold with air cooling method. The cast alloy designated as Mg9Al1Zn alloy received a solution treatment at temperature of 415 °C for 2 hours. The microstructure observation for the cast alloy showed the presence of α-Mg as a matrix with the largest fraction and β-Mg17Al12 phase as a precipitate. The microstructure also showed the presence of pores indicated by black colour. We have also undertaken microanalysis to each phase present in the sample by EDS that detected all elements. The result of Hardness evaluation confirmed that the solution treated as-cast alloys possessed the hardness value of 65.21. The VHN significantly enhanced when compared with that of original cast-alloy which was only 73.02 VHN. The enhancement of the hardness is discussed in relation with processing method and microstructure development after a solution treatment.