The surface area of the titanium dental implant materials can be increased by surface treatments without altering their shape and form, thereby increasing the biologic properties of the biomaterial. A good biomaterial helps in early cell adhesion and cell signaling. In this study, the commercially pure titanium surfaces were prepared to enable machined surfaces to form a control material and to be compared with sandblasted and acid-etched surfaces, laser treated surfaces and titanium dioxide (20 nm) Nano-particle coated surfaces. The surface elements were characterized. The biocompatibility was evaluated by cell culture in vitro using L929 fibroblasts. The results suggested that the titanium dioxide Nano-particle coated surfaces had good osteoconductivity and can be used as a potential method for coating the biomaterial.

Unidirectional abrasive flow finishing process was used to finish stainless steel SS316L and titanium alloy Ti-6Al-4V materials which are widely used as implant materials. Viscoelastic polymer-based flexible abrasive media was used to finish these surfaces with different pressure and number of cycles. The obtained surface roughness and surface topography were measured using profilometer, and morphology of the surface was studied using a scanning electron microscope. Further, the wettability of the finished surface was studied by measuring the contact angle (θ) for three liquids-water, formamide, and diiodomethane using the sessile drop technique. The measured contact angles were used to ascertain the surface free energy components using Van Oss Chaudhury-Good equation. Significant difference was observed on surface roughness, contact angle, and surface energy of the machined surfaces at different finishing cycles. Also, the different tendencies of the droplet contact angle and surface energy have been observed along the direction parallel and perpendicular to the finishing direction and it gave a strong conclusion that surface roughness and surface textures play a significant role in wetting characteristics. So, this work provides an overview of the interaction between droplet and surface topography of finished SS316L and Ti-6Al-4V surfaces. Further, an empirical model has been developed using the response surface methodology (RSM) for output responses namely, average surface roughness (R a ) and material removed (MR). Interactive effects of number of cycles and pressure on average surface roughness and material removed are discussed in this paper.

Fiber-reinforced composite (FRC), prostheses offer the potential advantages of optimized esthetics, low wear of the opposing dentition and the ability to bond the prosthesis to the abutment teeth, thereby compensating for less-than-optimal abutment tooth retention and resistance form. These prostheses are composed of two types of composite materials: Fiber-composites to build the substructure and hybrid or micro fill particulate composites to create the external veneer surface. This article reviews the various types of FRCs and its mechanical properties.

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Metal matrix composites (MMCs) play a vital role in today’s engineering industries. Stir casting is one of the most inexpensive methods for the production of particulate reinforced metal matrix composites. However there are few problems encountered in stir casting such as the problem of poor wettability of the reinforcement particles in the matrix metal. The reinforcement particles have the tendency to either settle at the bottom of the crucible or they tend to float at the top of molten metal. This is due to the greater surface tension of the molten metal. Various techniques are available to improve the wettability of the ceramic particles in metal matrix which includes Particle treatment, Particle coating and Addition of alloying agent. In this work, Magnesium (Mg) was used as the alloying element to improve the wettability of SiC particles in the Al matrix. Mg is used to reduce the surface tension of molten aluminum (Al) thus promoting proper wetting. To understand the effect of Mg on improving the wettability of SiC in aluminum matrix, different weight percentages of SiC particles reinforced aluminum alloy 6061(AA6061) based MMCs were fabricated in stir casting method by adding Mg as alloying element. The cast specimens were subjected to microstructural analysis, tension tests and hardness tests. Results showed that addition of Mg with SiC in AA6061 matrix significantly improved the wetting between Al and SiC; subsequently MMCs possessed enhanced mechanical properties.

Conventional monolithic materials have limitations in achieving good combination of strength, stiffness, toughness and density. To overcome these shortcomings and to meet the ever increasing demand of modern day technology, composites are most promising materials of recent interest. Metal matrix composites (MMCs) possess significantly improved properties including high specific strength, specific modulus, damping capacity and good wear resistance compared to unreinforced alloys. Among the MMC’s aluminum composites are predominant in use due to their low weight and high strength. The key features of MMC’s are specific strength and stiffness, excellent wear resistance, high electrical and thermal conductivity. The present investigation aims at the development of Aluminium based E-Glass and Flyash particulate reinforced hybrid metal matrix composites. The test specimens are prepared as per ASTM standard size by turning and facing operations to conduct tensile and compression test.

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