Search results for " wear"

A facially driven complete-mouth rehabilitation with ultrathin CAD-CAM composite resin veneers for a patient with severe tooth wear: A minimally inva…

2020

Abstract The development of technologies that include face scanning and dental software has improved workflows in dentistry. Digital files make it possible to create a 3-dimensional virtual image of the patient that helps the clinician plan treatment and make decisions, reducing uncertainty and improving communication. This report describes the complete-mouth rehabilitation of a patient with severe tooth wear. The treatment adopted a minimal intervention approach, applying adhesive veneers in areas where the tooth structure was affected and used a computer-aided design and computer-aided manufacturing (CAD-CAM) workflow to prepare nanoceramic composite resin materials with a high filler loa…

Electrochemical detection of chloride ions using Ag-based electrodes obtained from compact disc

2022

Abstract In this work electrochemical sensors fabricated from compact disc material (waste or new) are used to quantify chloride ions in different types of samples. All three electrodes, working, counter, and pseudo-reference electrodes, were fabricated from the compact disc and directly used. Different parameters were studied in order to demonstrate the possibility of using this waste material for efficient and low-cost electrochemical sensors. Chloride sensing performance was evaluated using linear scan voltammetry as the detection technique. A sensitivity of 0.174 mA mM−1 cm−2 with a limit of detection of 20 μM and excellent selectivity against many interferents was observed. Selectivity…

Use of positron annihilation measurements to detect the defect beneath worn surface of stainless steel 1.4301 (EN) under dry sliding condition

2012

Abstract Positron measurements were performed for detection of the subsurface zone in the stainless steel 1.4301 (EN) exposed to dry sliding. They revealed the defect profile induced by dry sliding which is extended inward the worn surface from 85 μm to 400 μm depending on the applied load during the tribo-test. This result was obtained using the positron techniques, while the microhardness profile exhibited shorter range of the microhardness depth profile, i.e., from 70 μm to 150 μm. However, at the depth of about 5 μm from the worn surface the sudden increase in the microhardness was observed. The complementary measurements of X-ray diffraction and SEM micrographs of the worn surface were…

ALE Simulation of Orthogonal Cutting: a New Approach to Model Heat Transfer Phenomena at the Tool-Chip Interface

2007

This paper presents a new procedure to evaluate the global heat transfer coefficient in orthogonal cutting. The knowledge of the actual heat transfer conditions is a fundamental issue as far as the life, tool wear and tool substitution interval are regarded. More in detail, an Arbitrary Lagrangian-Eulerian approach was utilised to model orthogonal cutting process and the numerical simulations were validated by making experimental tests for identifying cutting forces and internal tool temperatures. A mild steel was cut utilising both an uncoated (WC) and a coated (TiN) tool. On the basis of both experimental and simulative data, a consistent model of the global heat transfer coefficient as f…

3D finite element analysis of tool wear in machining

2008

Abstract The paper is focused on the 3D numerical prediction of tool wear in metal cutting operations. In particular, an analytical model, able to take into account the diffusive wear mechanism, was implemented through a specific subroutine. Furthermore, an advanced approach to model heat transfer phenomena at the tool–chip interface was included in the numerical simulation. The adopted simulation strategy gave the possibility to properly evaluate the tool wear. The 3D FEM results were compared with some experimental data obtained turning AISI 1045 steel using uncoated WC tool; a good agreement was found out.

Experimental characterization of bodycentric passive RFID systems

2011

Recent progresses in the design of wearable RFID tag antennas stimulate the idea of passive bodycentric systems wherein the required power to drive the wearable tags is directly scavenged from the interrogation signal emitted by the reader unit. While active bodycentric links have been extensively investigated, the feasibility of passive systems is still questionable due to the poor sensitivity of the tags and to the modest read distances. This paper describes an articulated measurement campaign with textile wearable low-profile tags in the UHF RFID band. It is demonstrated that both on-body and off-body links are feasible with a power budget fully compliant with the available technology. T…

Sensor-Assisted Machining

2008

This chapter provides comprehensive knowledge regarding the application of various sensors and monitoring techniques to machining processes, cutting tools and machine tools. A number of monitoring methods used in manufacturing and relevant sensors are characterized. In particular, three most frequently used sensors, i.e., force, acceleration and acoustic emission, are presented and their characteristics and advantages are highlighted. The architectures of multiple-sensor tool-monitoring systems for detection of tool wear and breakage and collision for machine tools, including details of sensor fusion, signal processing and decision-making, are presented. Moreover, the concepts of sensor-bas…

Feasibility of Body-centric Systems by Using passive textile RFID tags

2012

Recent progresses in the design of wearable RFID-tag antennas stimulate the idea of passive body-centric systems, wherein the required power to drive the wearable tags is directly scavenged from the interrogation signal emitted by the reader unit. While active body-centric links have been extensively investigated, the feasibility of passive systems is still questionable, due to the poor sensitivity of the tags and due to the modest reading distances. This paper describes a systematic measurement campaign involving low-profile wearable textile tags in the UHF RFID band. It was demonstrated that both on-body and off-body links are affordable, with a power budget fully compliant with the avail…

Prediction of Tool Wear in Machining

2007

On the effectiveness of Finite Element simulation of orthogonal cutting with particular reference to temperature prediction

2007

Abstract Finite Element simulation of orthogonal cutting is nowadays assuming a large relevance; in fact a very large number of papers may be found out in technical literature on this topic. In recent years, numerical simulation was performed to investigate various phenomena such as chip segmentation, force prediction and tool wear. On the other hand, some drawbacks have to be highlighted; due to the geometrical and computational complexity of the updated-Lagrangian formulation mostly used in FE codes, a cutting time of only a few milliseconds can be effectively simulated. Therefore, steady-state thermal conditions are not reached and the simulation of the thermal phenomenon may be ineffect…