This paper proposes a slurryless, highly efficient polishing method called ultrasonic vibration assisted electrochemical mechanical (UAECMP) to realize 4H–SiC wafers with subnanometer surface roughness. UAECMP involves using simultaneously assist anodic oxidation of the SiC and removal generated oxide layer. The performance was evaluated by experiments theoretical analyses. For (0001) surface, ...

In this work, ultrasonic vibration treatment (UVT) was introduced to improve the interfacial microstructure and bonding strength of A356/AZ91D bimetal processed via lost foam compound casting (LFCC). The mechanical properties Al/Mg LFCC with different UVT durations were investigated. Results revealed did not change composition phases at interface. bimetallic interface consisted an intermetallic...

Laser cladding was used to prepare three composite coatings, i.e., Inconel 718 nickel-based superalloy (IN718), IN718-50 wt.% WC created by adding tungsten carbide (WC) particles and assisted ultrasonic vibration. The phase composition, microstructure evolution, microhardness, residual stress tribological properties of the coatings were studied. addition enhances hardness improves properties, b...

Ultrasonic elliptical vibration cutting has recently been utilized in industry for finishing of various precision parts such as mirror surface finishing and precision micro machining of dies and molds. However, its application has been limited to high-cost ultra-precision machining, where depth of cut is typically in a range from a few micrometers to several tens of micrometers due to power lim...

The effect of mechanical stimulation of vibration on proliferation and differentiation of cells has been studied in vitro. To apply the vibration on the cells, a piezoelectric element was attached on the outside surface of the bottom of the culture plate of six wells. The piezoelectric element was vibrated by sinusoidally alternating voltage at 1.0 MHz generated by a function generator. Five ki...

Montmorillonite/ZrO2 nanocomposites were prepared by the sol-gel method underultrasonic irradiation. The montmorillonite was incorporated into Zirconium gel. After stirring for 24 hr, the mixture was irradiated for 30 min under ultrasonic irradiation. The filtrated composite gel was calcinated at 400°C for 3h in furnace. The morphology of prepared catalysts was characterized by field emis...

Acoustic streaming induced by ultrasonic flexural vibrations and the associated convection enhancement are investigated. Acoustic streaming pattern, streaming velocity, and associated heat transfer characteristics are experimentally observed. Moreover, analytical analysis based on Nyborg's formulation is performed along with computational fluid dynamics (CFD) simulation using a numerical solver...

Applications of power ultrasonics in engineering are growing and now encompass a wide variety of industrial processes and medical procedures. In the field of power ultrasonics, ultrasonic vibrations are used to effect a physical change in a medium. However, the mechanism by which a process can benefit from power ultrasonics is not common for all applications and can include one or more of such ...

The question of whether sound vibration of a medium can bring about any kind of molecular or macromolecular events is a long-standing scientific controversy. Although it is known that ultrasonic vibrations with frequencies of more than 1 MHz are able to align certain macromolecules in solution, no effect has yet been reported with audible sound, the frequency of which is much lower (20-20,000 H...