in this research, tribological characteristics of ni-p electroless coating and double-layered ni-p/ni-b electroless coating were studied. for this purpose, ni-p electroless coating with 25 μm thickness was initially applied to the surface of steel ck45 samples; then, a double-layered ni-p/ni-b electroless coating, including inner layer of ni-p with 15 μm thickness and outer layer of ni-b with 1...

Failure models based on the Palmgren-Miner concept that material darnage is cumulative have been derived and used mainly for fatigue life predictions for metals and composite materials. Wexeview the principles underlying such models and suggest ways in which they may be best applied to polymeric materials in temperature environments. We first outline expectations when polymer degradation data c...

Tyre wear is a complex phenomenon. It depends non-linearly on numerous parameters, like tyre compound and design, vehicle type and usage, road conditions and road sUliace characteristics, environmental conditions (e.g., temperature) and many others. Yet, tyre wear has many economic and ecological implications. The possibility to predict tyre wear is therefore of major importance to tyre manufac...

The wear mechanisms of cutting tools made of tungsten-carbide (WC), PCBN and PCD were investigated using the tool life and temperature results available in the literature. For tool/work combinations WC/steel and PCBN/hardened-steel, under practical conditions, tool wear was found to be greatly influenced by the temperature. It was concluded that the most likely dominant tool wear mechanism for ...

AIMS To determine the repeatability of ocular surface sensitivity to mechanical stimulation using air stimuli and the effect of contact lens (CL) wear on sensitivity. METHODS Repeatability: 14 subjects (24-39 years) participated. Mechanical sensitivity to warmed (34 degrees C) and ambient (20 degrees C) air was measured for the central cornea (CC), inferior cornea (IC), and inferior conjuncti...

Cr-Ni coatings with the mass ratios of 17% Cr-83% Ni, 20% Cr-80% Ni and 24% Cr-76% Ni were fabricated on H13 hot work mould steel using a laser cladding (LC). The surface-interface morphologies, chemical elements, surface roughness and phase composition of the obtained Cr-Ni coatings were analysed using a scanning electron microscope (SEM), energy disperse spectroscopy (EDS), atomic force micro...

In this investigation, MoSx/Cr coatings were deposited by direct-current magnetron sputter onto Ck45 (AISI 1045) plain carbon steel substrates. The MoSx/Cr ratio in the coatings was controlled by sputtering the composite targets. The chemical characterization was performed using EDX (energy dispersive X-ray analysis); the structural characterization was accomplished by X-ray diffraction (XRD) s...

A. D. Kelly General Signal Laboratory Equipment 275 Aiken Road Asheville, NC 28806 Low temperature refrigeration mechanically and thermally stresses a compressor's wrist journal bearing. Knowledge of bearing condition would be useful for self-diagnostics or predictive maintenance, particularly in freezers used for storage of valuable biomedical products. This initial investigation considers ext...

Simultaneous measurements of the curves for wear versus distance, wear rate versus distance, and coefficient of friction versus distance were performed in situ to distinguish the transition from severe running-in wear to mild wear. The effects of the initial surface roughness on the severe running-in wear volume were investigated. Disk-on-plate friction and wear tests were carried out with SUS3...

Nano-sized ceramic particle reinforced aluminum composites exhibit excellent room-temperature mechanical properties. However, there is limited research on the dry sliding wear behavior of those composites at elevated temperatures, which should be one of the major concerns on elevated temperature applications. Here the Al-Cu composites reinforced with nano-sized TiCp were fabricated. The dry sli...