A study on the combined effect of in-situ (TiC-TiB 2) reinforcement and aging treatment on the yield asymmetry of magnesium matrix composite

摘要

AbstractThe present work aims to study the individual as well as the combined effect of in-situ particles and precipitates on the tension-compression asymmetricity of AZ91 magnesium (Mg) alloy and AZ91?+?TiC-TiB2Mg matrix composites. Investigations have been done on four different material conditions: (a) alloy without particles or precipitates, (b) alloy with precipitates, (c) composite with particles, (d) composites with both particles and precipitates. Both the particle and precipitate significantly contribute towards lowering of tension to compression yield asymmetry. These particles/precipitates increase the critical stress for twinning by exerting a back stress which hinders the twin?propagation. Due to decrease in the twinning propensity, the tension to compression asymmetry reduces from 1.30 (at base condition) to 1.04 (peak aged condition of the composite). This phenomenon has been experimentally validated by means of tension and compression tests and the results have been correlated with the pre and post-deformation microstructures.Graphical abstractDisplay OmittedHighlights?A hybrid TiC-TiB2in-situ reinforced magnesium matrix is developed.?Effect of insitu particles and precipitates on yield asymmetry(R) is studied.?Presence of TiC-TiB2and precipitation lead to reduce R value in composite.?Reduction of R value is due to the back stress by precipitate and TiC-TiB2.]]>