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Showing 1 to 20 of 35 for “"Tungsten carbide"”.
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Tungsten carbide-cobalt by Three Dimensional Printing
… parts [Sachs, et al, 1990]. Green (not sintered) tungsten carbide-cobalt parts must have a density greater than 50% of the theoretical density, 14.9 g/cc, for proper sintering and post-processing. Two approaches were assessed for feasibility and robustness: printing slurry into tungsten …
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Erosion-corrosion resistance of tungsten carbide hard metals with different binder compositions
… erosion resistance of a series of cemented tungsten carbides with different binder compositions consisting of combinations of cobalt, nickel and chromium. Testing was carried out on a specially designed laboratory rig in both tap and salt water using silica sand as an erodent. The …
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The edge flaking of tungsten carbide hardmetal cermets under repetitive impact loading
Repetitive impact tests were carried out in order to determine the edge flaking performance of several grades of hardmetal cermets. In an attempt to understand the geometry and characteristics of the crack propagation glass was impacted. Various types of cracking are observed in the glass including …
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Slurry based Three Dimensional Printing (S-3DP tm) of tungsten carbide cobalt
Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Materials Science and Engineering, 2002.
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A comparative study on wear and corrosion behaviour of tungsten carbide-nickel (Wc-Ni) and tungsten carbide-cobalt (Wc-Co) high velocity oxy-fuel (HVOF) for carbon steel blade
… study is to characterize the structure of the tungsten carbide 10 wt.% nickel (WC-10Ni) and tungsten carbide 12 wt.% w cobalt (WC-12Co) coating deposited by means of HVOF thermal spray onto a continuous digester (CD) blade that made up from carbon steel. The morphology and chemical composition …
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Abnormal Grain Growth of Tungsten Carbide in Small Amount of Cobalt: Mechanism and Application
<P>CONSIDERABLE ABNORMAL GRAINS WERE OBSERVED IN LIQUID PHASE SINTERED CEMENTED WC WITH 0.2~0.9WT% COBALT. MICROSTRUCTURE EXAMINATIONS SHOWED GRAIN BOUNDARIES PARALLEL TO (0001) PLANES AND AGG WAS EXPLAINED BY GRAIN BOUNDARY RE-ENTRANT EDGE (GBRE) ASSISTED 2-D NUCLEATION PROCESS. GRAIN COALESCENCE …
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Vector drop-on-demand production of tungsten carbide-cobalt tooling inserts by three dimensional printing
… are examined as potential methods to produce Tungsten Carbide-Cobalt (WC-Co) tooling inserts. The research focuses on three fundamental process steps: (1) development of a stable slurry, (2) determination of jetting parameter values for optimal powderbed deposition, and (3) implementation of …
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A tribological study of a detonation gun coating of tungsten carbide for use in a subsea gate valve
Detonation gun coatings of tungsten carbide have been widely recognised as one of the most effective anti-wear coatings for oilfield applications. However, very little fundamental tribological information exists for the material, which hinders coating development and the evolution of correct …
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Development of a Microstructure-Level Finite Element Model for the Prediction of Tool Failure by Chipping in Tungsten Carbide-Cobalt Systems
The model has also been applied to a problem of WC-Co grade design for the improved performance. Validation experiments demonstrated the efficacy of model predictions. The simulation results agreed well with the observation found in the past literature that fatigue strength increases in a …
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Study of Pulse Electrochemical Micromachining using Cryogenically Treated Tungsten Microtools
… machining system ultra-high aspect ratio (400) tungsten microtools have been fabricated for wide range of applications from neural implants to deep micro hole drilling. Excessive wear was noticed during the application of these tools in the micromachining of difficult to machine tungsten …
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Long-term performance of pot hardware in continuous galvanizing lines
… CF3M (casting version of 316L steel), with tungsten carbide laser clad coating, at 30% and 50% production line tension. Tests were also conducted on Stellite 6 against Tribaloy T 400 at 50% production line tension. For each test, periodic measurements of wearing rate, surface microstructure …
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Machinability Study on Silicon Carbide Particle-Reinforced Aluminum Alloy Composite with CVD Diamond Coated Tools
… aluminum alloys reinforced with ceramic silicon carbide particles (AlSiC) require special cutting tools due to the high hardness and abrasive properties of the ceramic particles. Diamond coated cutting tools are ideal for machining this type of pMMC. Previous research studies focus on the …
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The wear of materials in an ash conditioner
… To optimise materials selection, a family of tungsten carbide-cobalt cermets together with a number of structural ceramics were tested in situ. The modes of wear can be related to material constitution. By ranking the performance of these candidate materials, value based materials selection …
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New catalysts for syngas production from carbon dioxide and methane
The performance of cobalt tungsten carbide material was investigated for CH4/CO2 reforming. The catalyst was found to convert to a very stable, very active, form when heated in CH4/CO 2 at 850°C and 5 atm. Even after 90 hours on stream, CH4 and CO2 rates of 1.3 and 1.25 mmol/min/g respectively …
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Vibrations of high-speed dental handpieces measured using laser vibrometry
… instrument (RCI), with a diamond RCI, or with a tungsten carbide bur. Repeated measurements were taken from six selected points on the handpiece. Further tests were performed to study the influence of increasing loads (50 to 200 g) whilst cutting into extracted human teeth. Results were …
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The machinability of a gamma titanium aluminide intermetallic
… on high speed milling trials using coated tungsten carbide ball nose end mills with various operating parameters whilst the second phase provided an assessment of intermittent dress creep feed grinding using both conventional (SiC) and superabrasive (diamond and CBN) wheels with free jet …
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Corrosion And Wear Resistance Of Titanium- And Aluminum- Based Metal Matrix Composites Fabricated By Direct Metal Laser Deposition
… with reinforcing powder blends of chromium carbide and tungsten carbide nickel alloy. Two powder formulations were investigated for each matrix material (Ti1, Ti2, Al1 and Al2). Titanium based composites were deposited onto a Ti6Al4V plate while aluminum composites were deposited onto AA …
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Infrared measurements of surface temperatures during oscillating/fretting contact with ceramics
… zirconium oxide, sapphire, aluminum oxide, and tungsten carbide were used as test specimens since they are inert in air, and generate high surface temperatures when used in the oscillating contact system. Instantaneous fluctuations in surface temperature over a single cycle were measured and …
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Tool selection and kitting : technical and organizational issues
… the aircraft. It was found that a double margin tungsten carbide (WC) cutter with a 1350 point angle and double margin design had superior cost and quality performance as compared to a 1180 point angle polycrystalline diamond (PCD) cutter with a single margin design that was previously used. For …
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