8 research outputs found
Ultrasonic dispersion of agglomerated particles in metal melt
This work considers the deagglomeration and wettability of particles by metal melt and proposes a mechanism of particle agglomerate dispersion by ultrasonic cavitation. The main dependences connecting the processing time and intensity with the physical and chemical properties of particles and the melt as well as acoustic parameters are obtained. For the first time found that melt during ultrasonic treatment, inclusive the particles agglomerates proportional to melt viscosity and the size of the agglomerates. It has been established that time ultrasonic treatment melt containing the particles agglomerates is proportional to melt viscosity and the size of the agglomerates. The required time for successful melt infiltration in the agglomerates, wettability and their introduction into the melt takes ten minutes. The suggested equation allows estimating the intensity of ultrasonic radiation, required to destroy the agglomerates of particles in the melt. It was found that intensity of the ultrasound must be inversely proportional to the radius of the agglomerates. The theoretical results are confirmed by comparing with experimental dates
Mechanisms of acoustic processing of a metal melt containing nanoparticles
Wave processing with the frequencies from subsound (vibration) to ultrasound is used to produce nanopowder-modified composite alloys. This work considers mechanisms of such processing of metal melts, which lead to deagglomeration and wettability of particles of a metal melt and to the destruction of growing crystals during solidification. The main dependences for the threshold of the turbulence and cavitation were obtained. Resonance phenomena that contribute to positive changes in the melt are discussed. Possible mechanisms of the destruction of growing crystals and agglomerates of particles at the high-frequency processing of the melt are considered, including the destruction of agglomerates in the front of an acoustic wave and the destruction of crystals by oscillating solid particles
Ultrasonic impact on a metal melt containing electrostaticly charged nanoparticles
Ultrasonic processing is applied to modify nanopowders of metals for the creation of composition alloys. The introduction of particles to metal is prevented by their low wettability in the metal melt. We use electrostatic charging of particles to increase the wettability of particles and to prevent their agglomeration. Mechanisms of the ultrasonic impact on melts of metals containing charged nanoparticles are considered. We find that an electric charge of the surface leads to a decrease in the contact angle. Expressions for the time of ultrasonic processing depending on physical and chemical characteristics of particles and the melt are found
Ultrasonic dispersion of agglomerated particles in metal melt
This work considers the deagglomeration and wettability of particles by metal melt and proposes a mechanism of particle agglomerate dispersion by ultrasonic cavitation. The main dependences connecting the processing time and intensity with the physical and chemical properties of particles and the melt as well as acoustic parameters are obtained. For the first time found that melt during ultrasonic treatment, inclusive the particles agglomerates proportional to melt viscosity and the size of the agglomerates. It has been established that time ultrasonic treatment melt containing the particles agglomerates is proportional to melt viscosity and the size of the agglomerates. The required time for successful melt infiltration in the agglomerates, wettability and their introduction into the melt takes ten minutes. The suggested equation allows estimating the intensity of ultrasonic radiation, required to destroy the agglomerates of particles in the melt. It was found that intensity of the ultrasound must be inversely proportional to the radius of the agglomerates. The theoretical results are confirmed by comparing with experimental dates
Mechanisms of acoustic processing of a metal melt containing nanoparticles
Wave processing with the frequencies from subsound (vibration) to ultrasound is used to produce nanopowder-modified composite alloys. This work considers mechanisms of such processing of metal melts, which lead to deagglomeration and wettability of particles of a metal melt and to the destruction of growing crystals during solidification. The main dependences for the threshold of the turbulence and cavitation were obtained. Resonance phenomena that contribute to positive changes in the melt are discussed. Possible mechanisms of the destruction of growing crystals and agglomerates of particles at the high-frequency processing of the melt are considered, including the destruction of agglomerates in the front of an acoustic wave and the destruction of crystals by oscillating solid particles
Ultrasonic impact on a metal melt containing electrostaticly charged nanoparticles
Ultrasonic processing is applied to modify nanopowders of metals for the creation of composition alloys. The introduction of particles to metal is prevented by their low wettability in the metal melt. We use electrostatic charging of particles to increase the wettability of particles and to prevent their agglomeration. Mechanisms of the ultrasonic impact on melts of metals containing charged nanoparticles are considered. We find that an electric charge of the surface leads to a decrease in the contact angle. Expressions for the time of ultrasonic processing depending on physical and chemical characteristics of particles and the melt are found