Effect of Different Cooling Rate on the Freezing Behavior of TiB₂/A356 Composite

Abstract:

The microstructure and tensile properties of TiB₂ particles reinforced A356 composite materials at different cooling rates are investigated. Experimental results show that the composition of the alloy solidification ,eutectic silicon content , morphology and size have undergone significant changes while the cooling rate increased: On one hand, α-phase grains significantly reduced, by a 50 μm average grain size refinement to 1~5μm with the evolution from coarse dendritic to rosette dendritic, or even spherical evolution; On the other hand, eutectic Si content increases, and diameter, aspect ratio also showed a decreasing trend, while the circularity is gradually increasing. Meanwhile, with the increasing of cooling rate, the particle distribution of TiB₂/A356 particle reinforced composite materials can be optimized. Particle aggregation is reduced, as a result TiB₂ particles’ reinforcement is more obvious, and the tensile fracture shows the obvious characteristics of ductile fracture.

• Periodical: Advanced Materials Research (Volume 1053)
• Pages: 157-164
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.1053.157
• Online since: October 2014
• Authors: Xiu Chuan Wu*, Yu Tao Zhao, Song Li Zhang, Kang Le Tian
• Keywords: Mechanical Property, Microstructure, Rapid Solidification, TiB₂ Particle Reinforced Composite Materials

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