EFFECT OF THE REINFORCEMENT PARTICLE SIZE ON THE COMPRESSIVE STRENGTH AND IMPACT TOUGHNESS OF LM29 ALLOY-B4C COMPOSITES
G. Pathalinga Prasad1,2, H.C. Chittappa2, M. Nagaral3, V. Auradi4
1)Department of Mechanical Engineering, AMC College of Engineering, Bangalore, Karnataka, India
2)Department of Mech. Eng., UVCE, Bangalore, India
3)Aircraft Research and Design Centre, Hindustan Aeronautics Limited, Bangalore, Karnataka, India,
4)Department of Mechanical Engineering, Siddaganga Institute of Technology, Tumkur, Karnataka, India
Investigations are made on the effect of 40 and 90 µm sized B4C particulate addition on compressive strength and impact toughness of LM29 alloy. Micro B4C particulates of 40 and 90 µm are used as reinforcements in the Al alloy matrix. Composites are prepared by using liquid melt method in steps of 3, 6 and 9 wt.% in the LM29 alloy. Samples are tested for microstructural characterization by using scanning electron microscope (SEM) and energy dispersive spectroscope (EDS). Mechanical properties as hardness, compression, and toughness are evaluated as per ASTM standards. SEM micrographs reveal the uniform distribution of B4C particulates in the LM29 alloy and are confirmed by EDS analysis. Further, compression and impact strength of base matrix LM29 alloy is enhanced with the addition of B4C reinforcement and is more evident in the case of 40 µm size reinforced composites.
Keywords: LM29 alloy, micro B4C, melt stirring, microstructure, strength, toughness