Experimental investigations of effects of SiC contents and severe plastic deformation on the microstructure and mechanical properties of SiCp/AZ61 magnesium metal matrix composites

• Published in: Journal of materials processing technology Vol. 272; pp. 28 - 39
• Main Authors: Huang, Song-Jeng, Ali, Addisu Negash
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 01.10.2019; Elsevier BV
• Subjects: Deformation effects; Equal channel angular pressing; Grain boundaries; Grain size distribution; Hardening rate; Magnesium; Magnesium base alloys; Magnesium compounds; Mechanical properties; Metal matrix composites; Metal silicides; Microstructural analysis; Microstructure; Modulus of elasticity; Particulate composites; Plastic deformation; Severe plastic deformation; Silicon carbide; Strain hardening; Work-hardening; Mechanical properties; Metal matrix composites; Severe plastic deformation; Microstructure; Work-hardening
• ISSN: 0924-0136; 1873-4774
• DOI: 10.1016/j.jmatprotec.2019.05.002

The objective of this research is to investigate the effects of equal channel angular pressing (ECAP) plastic deformation processes on the evolution of microstructural distributions and mechanical properties of SiC particles reinforced magnesium metal matrix composites (Mg MMCs). Investigations of the combined effects of the number of ECAP passes and SiC particles weight percentages were considered. The microstructural analysis results demonstrated a uniform distribution of matrix grain sizes and SiC particles (SiCp) segregation along the matrix grain boundaries as the number of ECAP passes increased. As the number of ECAP passes increased the presence and size of secondary phases were reduced at the pure AZ61 magnesium ally and 2 wt% SiCp/AZ61 Mg MMC. In the case of 5 wt% SiCp/AZ61 Mg MMC, the brittle Mg2Si secondary phase was observed and detected throughout the whole ECAP processes. The corresponding mechanical properties experimental investigation results confirmed that the elastic modulus was reduced by 47.98% for pure AZ61, increased by 5.38% for 2 wt% SiCp/AZ61 Mg MMC and increased by 25.9% for 5 wt% SiCp/AZ61 Mg MMC. The ECAP deformed 2 wt% SiCp/AZ61 Mg MMC showed the highest performance of strain hardening rate, strength and ductility.