• 文献标题:   Microstructure and mechanical characterizations of graphene nanoplatelets-reinforced Mg-Sr-Ca alloy as a novel composite in structural and biomedical applications
  • 文献类型:   Article
  • 作  者:   RAMEZANZADE S, EBRAHIMI GR, PARIZI MT, EZATPOUR HR
  • 作者关键词:   mgsrca alloy, graphene nanoplatelet, microstructure, mechanical propertie, strengthening mechanism
  • 出版物名称:   JOURNAL OF COMPOSITE MATERIALS
  • ISSN:   0021-9983 EI 1530-793X
  • 通讯作者地址:   Hakim Sabzevari Univ
  • 被引频次:   2
  • DOI:   10.1177/0021998319867464 EA AUG 2019
  • 出版年:   2020

▎ 摘  要

In this study, the novel composites were fabricated by the introduction of Mg-0.3Sr-0.3Ca alloy as the matrix and addition of different amounts of graphene nanoplatelets (0.1, 0.2, and 0.4 wt.%) as reinforcement using a stir casting technique followed by homogenization and extrusion in order to improve the mechanical properties of the base alloy. Optimum weight percent of adding graphene nanoplatelets was 0.2 wt.%. The addition of 0.2 wt.% graphene nanoplatelets in the extruded Mg-Sr-Ca alloy led to the grain refinement (similar to 36%), the decrease of anisotropy (similar to 14%) and the lowest twin formation. Moreover, the tensile and compressive yield strengths and tensile and compressive fracture strains of extruded Mg-0.3Sr-0.3Ca/0.2GNP composite were enhanced by 22.8%, 66.7%, 43.1% and 28%, respectively. The load transfer was significant strengthening mechanism. The uniform dispersion of graphene nanoplatelets followed by the increase of non-basal slip and grain refinement improved tensile fracture strain. In addition to maintained factors, the increase of compressive fracture strain in the extruded Mg-0.3Sr-0.3Ca/0.2GNP composite was affected by local stresses caused by twins which resulted non-basal slip and conserved basal slip due to presence of twins. Simultaneously, enhancement of the strengthening and elongation efficiencies in both tensile and compressive tests was achieved in Mg-0.3Ca-0.3Sr/0.2GNP. The biocorrosion behavior of extruded Mg-0.3Sr-0.3Ca/0.2GNP composite was promoted by 11% compared with Mg-0.3Sr-0.3Ca alloy. Comparative plots indicated that the fabricated materials can be introduced as a new class of composites for the purpose of structural as well as biomedical applications.