The techniques for estimating the adhesive and cohesive strength in high velocity oxy fuel (HVOF) thermal spray coatings have been discussed and compared. The development trend and the last investigation have been studied. We will focus on benefits and limitations of these methods in different process and materials. Keywords—Adhesion, Bonding strength, Cohesion, HVOF Thermal spray

We report here on the results of experiments concerning particular bonding processes potentially useful for ultimate miniaturization of microfluidic systems. Direct anodic bonding of continuous thin Pyrex glass of 250 pm thickness to silicon substrates gives multiple, large voids in the glass. Etchback of thick glass of 1200 pm thickness bonded to silicon substrates gives thin continuous glass ...

We employ first-principles density functional calculations to explore atomic-level interactions and predict the ideal work of adhesion at the SiO2/nickel and ZrO2/SiO2 interfaces. We find that chemical bonding at the interface serves to strengthen significantly interfaces formed with SiO2, which exhibits significant covalent bonding character, relative to those formed using more ionic oxides, s...

We report the demonstration of a terahertz quantum-cascade laser that operates up to 164 K in pulsed mode and 117 K in continuous-wave mode at approximately 3.0 THz. The active region was based on a resonant-phonon depopulation scheme and a metal-metal waveguide was used for modal confinement. Copper to copper thermocompression wafer bonding was used to fabricate the waveguide, which displayed ...

Anodic bonding of silicon to glass always involves heating the glass and device to high temperatures so that cations become mobile in the electric field. We present a simple way of bonding thin silicon samples to borosilicate glass by means of heating from the glass side while locally cooling heat-sensitive areas from the silicon side. Despite the high thermal conductivity of silicon, this meth...

Thermal wetting can simply, selectively and reversibly join patchy particles into clusters (2D and 3D) and also colloidal crystals over the narrow temperature range of 1-2 °C. This is demonstrated with Janus particles (gold half-coated silica spheres) immersed in a binary mixture of water/2,6-lutidine, such that the relative strength of gold-gold bonding through hydrophobic interaction and sili...

A series of (MS)1+x(TiS2)2 (M = Pb, Bi, Sn) misfit layer compounds are proposed as bulk thermoelectric materials. They are composed of alternating rock-salt-type MS layers and paired trigonal anti-prismatic TiS2 layers with a van der Waals gap. This naturally modulated structure shows low lattice thermal conductivity close to or even lower than the predicted minimum thermal conductivity. Measur...

Manipulating thermal transport across hard/soft material interfaces is important for composites which are critical for a wide range of applications, including electronic packaging, thermal storage, sensors and medicine. To increase the interfacial thermal conductance (Gint), a previous strategy has focused on using a self-assembled monolayer (SAM) to bridge the phonon spectra mismatch between t...