Recent Advances in Dental Composites: An Overview

Composite resins are widely used aesthetic materials in restorative dentistry. These materials were introduced to overcome the inherent shortcomings of amalgam restorative materials. Dental amalgams are unesthetic and toxic. Earlier composites lack in mechanical properties to withstand the masticatory forces. Various filler particles have been added to composite resins to improve their physical and mechanical properties.  Filled composite resins exhibit high compressive strength, abrasion resistance, ease of application and high translucency. Depending on the filler size and shapes, various composites have been developed until now. This article is a review of numerous types of composites that are technologically advanced to modify their properties

Design optimization and testing of electrical connector for low voltage transmission cabinets : In collaboration with ABB AB Kabeldon

Abstract: This thesis work was a part of Halmstad University’s Mechanical Masterprogramme curriculum done in favour of ABB Alingsås. Our industrial partnerproduces and manufactures low voltage electrical distribution cabinets, connectorsand switch gears. This project is focused on specific electrical connector used inABB’s trademark cabinets. These electrical connectors serve as both the input and output points for thedistribution cabinets. The product under scope is an extension connector calledADI3M which is used in conjunction with the large sized cable connectors(AD300). This is a sequential design optimization activity performed after theredesigning of the AD300 to ensure interface compatibility and also aimed atopportunistic cost reduction. The ADI3M should provide design compatibility withboth old and new AD300 connector designs along with the comfortable interfacinginside the CDC and SDC cabinets. With the design process and concepting knowledge gained from the course work inHalmstad university along with the ABB’s industrial exposure towards the powersupply networks we proposed four different design concepts. These design conceptswere then evaluated against interface compatibility, cost aspects, manufacturingreadiness, mechanical strength, heat generation and electricity conductionproperties. Among the product development techniques, we applied QFD processto generate the concepts, waterfall method to frame the engineering design processflow and morphological matrix to select the generated concepts. We then changedthe raw material from brass to aluminium and extrusion process due to its beneficialproperties compared to brass and copper with various other reasons explainedclearly in the thesis content. For the plastic cover we preferred poly-carbonate dueto requirements such as transparency, stiffness, etc. Two of the best feasibleconcepts were selected and the design proposals were prototyped using 3D printingtechnology. The 3D printing method used was fused deposition modelling (FDM).Later machined aluminium prototypes were then produced for the metalsubcomponents to do real time strength analysis and interface checks. Weperformed a theoretical product strength analysis using ANSYS19.2. Then resultswere then evaluated, and the final concept was chosen according to the factors suchas cost impact, easy installation and comfortable inter-component clearance.Finally, the prototypes were tested for IP rating fulfilment and compatible interfaceswith adjacent components. The consecutive activities to be done out of thesis scope is to conduct mechanicaland tests and record the performance. The future scope of this project is to developa hybrid design combining the AD300 and ADI3M connectors which would enableeasy product handling, simplified functionality and further reduce cost