In forming tungsten carbide layer by low temperature and vacuum CVD, uniformity of film thickness, adhesion and gloss achieved when the effective zone of coating set is increased to 4450 x 1,100mm is described. Characteristics of tungsten carbide layer are evaluated and compared with other materials. Some practical applications to the mechanical parts of plastic injection molding machines are i...

The Ni-based coatings with different content of spherical tungsten carbide were deposited by plasma transfer arc welding (PTAW) method on 304 austenitic stainless steel sheets in this study. The microstructure and wear property of spherical tungsten carbide particle reinforced composite coatings were investigated by means of optical microscope, scanning electron microscope (SEM), X-ray diffract...

The present research concerns an electrodeposited cobalt-tungsten alloy coating on graphite fibers. Annealed and unannealed coated fibers were analyzed by scanning electron microscopy/energy dispersive x-ray spectroscopy (SEM/EDS), x-ray diffraction (XRD), and transmission electron microscopy (TEM). The mole fraction of tungsten in the as-deposited cobalt-tungsten coating was found to be (7.10 ...

Interface delamination is the major weakness limiting diamond coating tool performance in machining. Thus, quantitative characterizations of the interface behavior are important to better understand and design diamond coating tools. In this study, we attempt to apply a cohesive zone model to investigate the coating-substrate interface behavior. The cohesive zone model is based on the traction-s...

Since the cutting tools used in machining process of super alloys are subjected to high cutting forces, accordingly tools life is reduced, therefore improvement in alloys machining and reducing cutting forces to achieve longer tools life is an essential necessity. In this research, the effect of changes in feed rate on cutting forces in machining process of nickel based super alloys is investig...

Tribological coatings made of MoS2 and WSe2 phases and their corresponding combinations with tungsten carbide (WC) were prepared by non-reactive magnetron sputtering of individual targets of similar composition. A comparative tribological analysis of these multiphase coatings was done in both ambient air (30-40% relative humidity, RH) and dry nitrogen (RH<7%) environments using the same tribome...

OBJECTIVES The aim of this study was to determine the apical surface characteristics and presence of dental cracks in single-rooted premolars, resected 3.0 mm from the root apex, using the Er: YAG laser, tungsten carbide bur, and diamond-coated tip, by scanning electron microscopy (SEM). EXPERIMENTAL DESIGN Thirty single-rooted premolar teeth were collected. The instrumented and obturated tee...

This investigation originated in a report by Dr. Joan Cotterill, one of H.M. medical inspectors of factories, that workers in a Midlands factory making hard cutting tools complained of shortness of breath and that in radiographs of their lungs, some of them showed abnormal shadows. Many of the processes in the factory are trade secrets, but it is known that powdered cobalt metal is used as a bo...

In this study, the effect of cladded tungsten carbide layer upon HSS - M2 tool steel on microstructure, hardness, and wear behavior has been studied in two cases without using the middle layer and using the middle layer of nickel. Tungsten Carbide cladded on HSS - M2 tool steel by Arc Weld ( SMAW ). The ASTM-G65 wear test was used to determine its application for use in the mineral indus...

The role of elastic mismatch in determining critical conditions for indentation fracture in brittle coatings on substrates of unlike modulus was investigated. A model transparent trilayer system, consisting of a glass coating layer bonded to a thick substrate of different glass or polymer by a thin layer of epoxy adhesive, facilitated in situ observations of crack initiation and propagation. A ...