DINESHSINGH G THAKUR
Articles written in Sadhana
Volume 46 All articles Published: 2 February 2021 Article ID 0011
Aluminum matrix composites are being widely used in aircrafts due to high strength to weight ratio, good tribological properties and better castability. The B4C particles have low density, high hardness, high strength and stiffness. The poor wettability is major challenge during the fabrication of Al-B4C composite. To overcome this problem, titanium based flux (K2TiF6) was used to improve the wettability. In this study, structurally efficient Al-Li 8090 alloy containing 2, 5 and 10 wt% of B4C particles were fabricated by using modified stir casting technique with an objective to obtain homogenous dispersion of B4C particles in the matrix. The microstructures evaluation was done to know the distribution of particulates in the matrix. The influence of particle volume content on the mechanical and wear behavior of composites has been investigated. The ultimate tensile strength, micro and macro hardness, high temperature hardness and wear characteristics have been investigated. Ageing behavior, XRD analysis and fractography of the composites has also been studied. The outcome of the experimental investigation revealed that, 2% B4C particulate reinforced composite exhibits better mechanical, physical and tribological properties. 10% B4C particulate reinforced composite shows clustering and agglomeration at some local regions causing a drop in the properties..
Volume 46 All articles Published: 30 July 2021 Article ID 0151
Additive Manufacturing (AM) has the ability to fabricate complex structures with bio-mimicry features. Fused Deposition Modeling (FDM), which is AM technique, has the capability of creating complex geometry parts in a short time. The mechanical properties of FDM build parts can be improved by selecting theproper printing parameters. In the present study, the effect of printing parameters viz. printing orientation (flat and on-edge) and infill density (20%, 35%, 50%, 65%, 80% and 100%) on the impact strength of bio-inspired 3Dprinted specimen has been studied. The specimens with multi-infill pattern were inspired by bio-inspired structure like a turtle shell. The multi-infill pattern specimen includes triangular, honeycomb and grid infill patterns. Based on this multi-infill pattern, impact specimens were fabricated and tested. Impact strength and impact strength/weight ratio of specimens in flat and on-edge orientation are measured and evaluated. The result shows that the impact strength and impact strength/weight ratio of multi-infill pattern specimens printed in flat orientation is less compared to specimens printed in on-edge orientation. The multi-infill pattern specimen with 20% infill density printed in on-edge orientation has the highest impact strength and impact strength/weight ratio as compared to other specimens. Further, high magnification fracture surface analysis is performed to aid in the characterisation of specimen failures.