Ex-situ and in-situ Metal Matrix Composites

Ex-situ composites

Introduction:

In ex-situ composites, reinforcements are synthesised externally and than added into the matrix during composite fabrication.

Description:

In this work, powder metallurgy route was used to fabricate the composites. Commercial available SiC and Al₂O₃ particles are added to the AA7075 Al alloy matrix powder and mixed well, than the compacted powder was sintered to get better microstructure. These composites were synthesised with different particle size and volume fraction of the reinforcement. Mechanical and tribological properties are evaluated and correlated with the microstructure. Statistical analysis technique was used in this study.

In-situ composites

Introduction:

In in-situ composites, reinforcements are synthesised internally in the matrix during the composite fabrication.

Description:

In this work, mixed salt reaction casting route was established to get in-situ composites. K₂TiF₆ and KBF₄ salts are added to the liquid Al to yield Al-TiB₂ in-situ composites, whereas K₂TiF₆ and graphite are added to liquid Al to get Al-TiC. These research was carried out on various binary (Al-4Cu, Al-7Si) and commercial (A356) Al alloys with different volume fraction of in-situ formed reinforcements (TiB₂ and TiC). Mechanical and tribological properties of these composites are much superior to the base matrix alloy.

AA7075 Al-SiC AA7075 Al-Al₂O₃

I started to work on this topic from 2002 as a part of my Master programme with Prof V.Balasubramanian, for further details of the work please refer to the publication list.

Al-4Cu-TiB₂ Al-4Cu-TiC

I started to work on this topic from 2004 as a part of my PhD programme with Prof B.S.Murty and Dr V.Subramanya Sarma, for further details of the work please refer to the publication list.