Fatigue behavior of case hardened parts depend to a great extent on the type of residual stresses developed in the components. Topography and metallurgical effects were the two elements which contribute much to surface integrity. Micro hardness of the gas carburized (EN 33 and EN 36) and Induction hardened (AISI 1040 and AISI 6150) specimens obtained during experiments, showed that there was gr...

This study investigated the softening and erosive effects of various paediatric over-the-counter (OTC) oral liquids on deciduous teeth. Twenty sectioned and polished deciduous enamel blocks were ground on the buccal surface (2 × 2 mm²) and randomly divided into five groups, immersed into four commercially-available paediatric OTC oral liquids (two for paracetamol, both sugared; and two for chlo...

BACKGROUND The objective of this study was to study the potential protection effect of different treatments against sound enamel demineralization around orthodontic brackets. METHODS This is an in vitro randomized controlled study; artificial enamel demineralization of human premolars was created and compared with reference to control. The three materials used for enamel treatment were resin ...

In the present study, the hardness and electrical properties of copper based composite prepared by hot pressing of mechanically alloyed powders were predicted using Artificial Neural Network (ANN) approach. Milling time (t, h), particles size of mechanically alloyed powders (d, nm), dislocation density (ρ, m) and compressive yield stress (σ0.2, MPa) were used as inputs. The ANN model was develo...

Purpose: This paper presents an efficient and reliable swarm intelligence-based approach, namely particle swarm optimization [PSO] technique, to optimize the hardness and the parameters that affect the hardness in the Ni-Diamond composite coatings. Design/methodology/approach: Particle swarm optimizers are inherently distributed algorithms, in which the solution for a problem emerges from the i...

A group of Stellite alloys are studied in consideration of temperature effects on their hardness and wear resistance. The hardness test is conducted on a micro-hardness tester with a hot stage equipped that allows heating the specimen up to 650°C. The wear resistance of each alloy is evaluated using a pin-on-disc tribometer with a heating furnace built-in that provides the temperature capacity ...

Objective: This in vitro study examined the ability of Forté, based upon co-catalyzed calcium peroxide and carbamide peroxide (CaCP), to remineralize and recalcify pre-existing incipient lesions in tooth enamel, renewing the teeth while they are being whitened. • Methodology: Artificial lesions to 70-100 micrometers depth were created, simulating in vivo conditions. Calcium concentrations were ...

The aim of this work was a scanning electron microscopy (SEM) evaluation of the hardness and morphological changes of enamel irradiated by neodymium: yttrium aluminium garnet (Nd:YAG) laser with different energy levels. Twenty-eight human teeth samples were divided into 4 groups: control, where enamel surface was not lased, and 3 test treated with 3 different levels of energy power 0.6, 1.2 and...