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...

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...

background: titanium (ti) implants are commonly coated with hydroxyapatite (ha). however, ha has some disadvantages such as brittleness, low tensile strength and fracture toughness. it is desirable to combine the excellent mechanical properties of zro2 and the chemical inertness of al2o3 with respect to the purpose of this project which was coating ti implants with ha-zro2-al2o3 to modify the s...

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...

Ultra-thin diamond-like carbon (DLC) coatings are used in hard disk drives to protect the intricate magnetic structures from wear and corrosion. The coating on the recording head consists of a hard DLC layer and a silicon (Si) layer that improves adhesion between the DLC layer and the substrate. Damage to this protective coating can expose the magnetic structures to corrosion and compromise the...

despite having some useful properties, stainless steels suffer from lack of suitable surface hardness. in this research electroless ni-b-tl coating was used with the aim to increase their surface hardness. the effects of nickel chloride, sodium borohydride, thallium nitrate and ethylendiamin on the chemical composition of coating were studied. to achieve an increase in hardness, the effects of ...

An optimized graded-refractive-index (GRIN) antireflection (AR) coating with broadband and omnidirectional characteristics--as desired for solar cell applications--designed by a genetic algorithm is presented. The optimized three-layer GRIN AR coating consists of a dense TiO2 and two nanoporous SiO2 layers fabricated using oblique-angle deposition. The normal incidence reflectance of the three-...