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Plasma electrolytic oxidation (PEO) is an advance technique to develop porous oxidation layer on light metals, primarily to enhance corrosion and wear resistance. The oxidation layer can also offer a wide variety of mechanical, biomedical, tribological, and antibacterial properties through the incorporation of several ions and particles. Due to the increasing need of antimicrobial surfaces for biomedical implants, antibacterial PEO coatings have been developed through the incorporation of antibacterial agents. Metallic nanoparticles that have been employed most widely as antibacterial agents are reported to demonstrate serious health and environmental threats. To overcome the current limitations of these coatings, there is a significant need to develop antibacterial surfaces that are not harmful for patient's health and environment. Attention of the readers has been directed to utilize bioactive glasses as antibacterial agents for PEO coatings. Bioactive glasses are well known for their excellent bioactivity, biocompatibility, and antibacterial character. PEO coatings incorporated with bioactive glasses can provide environment-friendly antimicrobial surfaces with exceptional bioactivity, biocompatibility, and osseointegration. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 106A: 590-605, 2018.

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Drilling two different materials in a layer, or stack-up, is being practiced widely in the aerospace industry to minimize critical dimension mismatch and error in the subsequent assembly process, but the compatibility of the drill to compensate the widely differing properties of composite is still a major challenge to the industry. In this paper, the effect of customized twist drill geometry and drilling parameters are being investigated based on the thrust force signature generated during the drilling of CFRP/Al7075-T6. Based on ANOVA, it is found that the maximum thrust force for both CFRP and Al7075-T6 are highly dependent on the feed rate. Through the analysis of maximum thrust force, supported by hole diameter error, hole surface roughness, and chip formation, it is found that the optimum tool parameters selection includes a helix angle of 30°, primary clearance angle of 6°, point angle of 130°, chisel edge angle of 30°, speed of 2600 rev/min and feed rate of 0.05 mm/rev. The optimum parameters obtained in this study are benchmarked against existing industry practice of the capability to produce higher hole quality and efficiency, which is set at 2600 rev/min for speed and 0.1 mm/rev for feed rate.

The high performance and downsizing technology of three-dimensional integrated circuits (3D-ICs) for mobile consumer electronic products have gained much attention in the microelectronics industry. This has been driven by the utilization of chip stacking by through-Si-via and solder microbumps. Pb-free solder microbumps are intended to replace conventional Pb-containing solder joints due to the rising awareness of environmental preservation. The use of low-volume solder microbumps has led to crucial constraints that cause several reliability issues, including excessive intermetallic compounds (IMCs) formation and solder microbump embrittlement due to IMCs growth. This article reviews technologies related to 3D-ICs, IMCs formation mechanisms and reliability issues concerning IMCs with Pb-free solder microbumps. Finally, future outlook on the potential growth of research in this area is discussed.