Laser printing of silver-based micro-wires in ZrO2 substrate for smart implant applications

Smart implants are endowed with functions of sensing, actuating and control to solve problems that may arise during their use. The assembly of these functions along the implant surface is still a challenge. However, with the advent of 3D printing, it is possible to print on implants’ surface, communication channels or micro-antennas or even sensoric/actuating areas. Hence, a positive impact on the long-term performance of the implants (including hip, dental and knee) may be expected with the proposed approach. Despite titanium and Ti6Al4V titanium alloy are the standard choice for implants fabrication, 3Y-TZP (tetragonal 3% mol yttria-stabilized zirconia) has emerged as a ceramic material suitable to overcome titanium alloy problems, due to its numerous advantages. In this sense, this work is concerned with the ability of printing silver-based communication system in zirconia substrates by using laser technology. For this purpose, micro-cavities were created on ZrO2 substrate, where the silver powder was placed and sintered into them. Through the laser approach, silver-based wires with great quality and low resistivity values were achieved. The flexural strength results showed that the mechanical resistance of zirconia disks was affected by laser micro-wire printing, which decreased as the laser passage was performed. Based on the results, it is believed that the proposed approach seems to be effective for the manufacturing of implants with intrinsic capacities, useful for smart implant applications.This work has been supported by FCT (Fundação para a Ciência e Tecnologia - Portugal) in the scope of the projects UID/EEA/04436/ 2019 and NORTE-01-0145-FEDER-000018-HAMaBICo and Add.Additive_Manufacturing to Portuguese Industry_POCI-01-0247- FEDER-024533. Thank the CNPq (205791/2014-0) and CAPES for the financial support

A miniature bio-inspired optic flow sensor based on low temperature co-fired ceramics (LTCC) technology

International audienceLow temperature co-fired ceramics (LTCC) technology is classically used in the field of radio frequencies to make items such as miniature transceivers for handheld devices. Here we harness the LTCC technology to autonomous micro-aerial vehicles (MAVs), a field in which small size and low mass are at a premium. Designing autonomous MAVs will be a highly challenging issue during the next few decades. Bio-inspired optic flow sensors, also known as elementary motion detector (EMD) circuits, have proved to be efficient means of providing animals and robots with visual guidance ability. The LTCC technology gives a good trade-off between the need for reliable optic flow sensors and the need for small-sized multiple electronic components. Comparisons with other technologies (PCB, analogue VLSI) show that LTCC technology is one of the most reliable solutions to the problem of obtaining reliable electronic EMDs that are small enough (area 7 mm x 7 mm) and light enough (mass 0.2 g) to be accommodated on-board a MAV. The output from our LTCC based optic flow sensors is largely invariant with respect to both contrast and spatial frequency. (c) 2006 Elsevier B.V. All rights reserved