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...

Alternative approaches to evaluating the hardness and elastic properties of materials exhibiting physical properties comparable to pure diamond have recently become necessary. The classic linear relationship between shear modulus (G) and Vickers hardness (HV), along with more recent non-linear formulations based on Pugh's modulus extending into the superhard region (HV > 40 GPa) have guided syn...

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 purpose of this study was to evaluate hardness (indicator for polymerization) and thickness of two types of resin cement at coronal, middle and apical level of tooth root canal. Ten extracted maxillary incisors were instrumented and post space was prepared for cementation of titanium post. Samples were divided into two groups and each group was cemented either of the two types of resin ceme...

Introduction: The degree of polymerization depends on the type of light-curing unit. The aim of this study was to compare the hardness of composite resin cured by LED and Halogen light curing units. Methods: In this experimental study, 20 cylindrical samples of Tetric Ceram composite were prepared. Half of them were cured with Ultralume 2 LED and the other half with Astralis 7 Halogen light cur...

OBJECTIVES The aim of this study was to evaluate the mechanical and physical properties of a newly developed fiber reinforced dental composite. MATERIALS AND METHODS Fiber reinforced composite EverX Posterior (EXP, GC EUROPE), and other commercially available bulk fill composites, including Filtek Bulk Fill (FB, 3M ESPE), SonicFill (SF, Kerr Corp.), SureFil (SDR, Dentsply), Venus Bulk Fill (V...

The effects of HfB₂ and HfN additions on the microstructures and mechanical properties of TiB₂-based ceramic tool materials were investigated. The results showed that the HfB₂ additive not only can inhibit the TiB₂ grain growth but can also change the morphology of some TiB₂ grains from bigger polygons to smaller polygons or longer ovals that are advantageous for forming a relatively fine micro...

OBJECTIVE Depth of cure of composite material is restricted and it depends on many parameters such as thickness. The aim of this in-vitro study was to evaluate the depth of cure of two light-cured core build-up composites (Quixfil and Photocore) in different thicknesses, when cured for 60 seconds. MATERIALS AND METHODS The Vickers microhardness measurements were made for each side of the top ...

This paper describes the process used by Consultative Committee for Mass and Related Quantities - Working Group on Hardness (CCM-WGH) of International Weights Measures (CIPM) to develop international definitions conventional Rockwell, Brinell, Vickers Knoop hardness test methods, use National Metrology Institutes (NMI) that standardize measurement.