Ultrasonic Atomization as a Novel Route for the Metal Powder Development (original) (raw)

Production of fine powders by ultrasonic standing wave atomization

Powder Technology, 1996

Ultrasonic standing-wave atomization using two sonolrocles (20 kHzL both osciltating against each other, allows the disintegration of extremely viscoes fluids (synthetic resins, highly concentrated suspensions) or fluids with high surface tension (metal melts) into narrowsized, extremely small droplets and therefrom the production of fine spherical powders. The fundamentals of this new technique as well as its application in viscous fluid and melt alomizatioa are described. Rapid sotidification rates of metal powders (lin panicles with mean diameters oflesslhan 10pro) upto2×10 ~K~sf~rachievingu~ra-~ec~u~armicr~stm~ureswi~hin~hepowde~pani~esa~d~th~s.f~rinstsnc~ supersaturation effects ate further important advantages of this lechnique.

Novel Cold Crucible Ultrasonic Atomization Powder Production Method for 3D Printing

2021

A new powder production method has been developed to speed up the search for novel alloys for additive manufacturing. The technique involves an ultrasonically agitated cold crucible installed at the top of a 20 kHz ultrasonic sonotrode. The material is melted with an electric arc and undergoes pulverization with standing wave vibrations. Several different alloys in various forms, including noble and metallic glass alloys, were chosen to test the process. The atomized particles showed exceptional sphericity, while powder output suitable for additive manufacturing reached up to 60%. The AMZ4 metallic glass powder remained amorphous below the 50 μm fraction, while tungsten addition led to crystallization in each fraction. Minor contamination and high Mn and Zn evaporation, especially in the finest particles, was observed in atomized powders. The innovative ultrasonic atomization method appears as a promising tool for material scientists to develop powders with tailored chemical composi...

Atomization process for metal powder

Materials Science and Engineering: A, 2004

A new atomization process has been developed, which combines pressure and gas atomization. The melt leaves the pressure nozzle as a hollow thin film cone. After the pre-filming step, the melt is atomized by a gas stream delivered by a ring nozzle. The objectives of this investigation are to achieve a narrow size distribution and low specific gas consumption compared to conventional gas atomization techniques. Both lead to a higher efficiency and low costs. Tin and some alloys have been atomized successfully with this technique. The mass median diameters from different experiments are between 20 and 100 m. Sieving analysis of the tin powder shows close particle size distributions.

Design and Construction of Water Atomizer for Making Metal Powder

Journal of metals, materials and minerals, 2011

Water Atomization for metal powder is an appropriate method for producing metal powder from different kinds of metal. Typically, a water atomizing machine is designed with a molten metal spraying chamber in a vertical or horizontal orientation depending on a nozzle design, a molten metal spraying chamber and related components. The main variables influencing the working condition of the water atomization process, which affect sizes, shapes and distribution of metal powder particles, are water pressure, water flow rate, a temperature higher than melting point of liquid metal and flow rate of liquid metal. The water atomizing machine in the study was designed and constructed in which the variable values mentioned could be adjusted. The metal powder produced with the water atomizing machine was from copper, low carbon steel and AISI 304-stainless steel. The result indicates that the water atomizing machine was able to produce the intended metal powders from different kinds of metal. Th...

Mechanical alloying of powder materials by ultrasonic milling

Ultrasonics, 2004

An ultrasonic grinding mill was designed. It permits to carry out simultaneously intensive ultrasonic, mechanical and cavitation treatments of powder materials that in turn leads to sharp acceleration of diffusion, mass-transfer processes and solid phase reactions due to crystallite size and structure changing. It was shown that meta-stable non-equilibrium solid solution (Cu+Ni+Fe, Fe+C), and crystalline structure transformed (Fe(4)N: fcc-hcp transformation) powders could be obtained for the much shorter time in compare with traditional mechanical alloying in planetary ball mill.

Scale up of ultrasonic spray pyrolysis process for nano- powder production -Part I

2013

Nanostructured materials and their application have been one of main research topics in the last decades. Various nanomaterials and endless application of them is known today. On the other hand, industrial application of nanomaterials is still challenged with limited offer of methods suitable for big scale nanomaterials production, especially when it comes to nanomaterials with target morphology and complex composition. In this paper is presented a report on scale up of Ultrasonic Spray Pyrolysis (USP) process. The USP as the nanoparticle production method is relatively inexpensive and quite versatile technique based on an aerosol process to produce fine metallic, oxidic, composite nanoparticles of precisely controlled morphology and defined chemical compositions from water solution using different metal salts and their mixtures [1-4].

1 Economic Additive Manufacturing using Water Atomized Stainless Steel Powder

2017

316L stainless steels are highly corrosion resistant steels utilized in applications ranging from handling chemicals in the process industry, pharmaceuticals, medical implants, to automotive applications. This stainless steel is characterized by good formability, weldability, and exceptional toughness. Primary alloying elements, chromium, nickel, and molybdenum provide exceptional resistance to corrosion. Due to these desirable qualities, 316L is an attractive alloy for Additive Manufacturing (AM). Essential powder characteristics (e.g. flowability, morphology) for AM are still being developed and understood. Gas atomization (GA) is the principle production route for powder aimed towards AM. Water atomization (WA) is another means to produce powder, albeit, with morphological and chemical characteristics slightly different to GA powder. This paper presents the morphological, microstructural, and mechanical properties of WA compared to GA 316L after being processed via Selective Lase...

Characterization of NiCu alloy powders produced by the atomization process

Materials Science and Engineering: A, 1991

The atomization techniques is an extensive way for producing rapidly cooled metal powders. This paper presents an experimental study of some process parameters on the powder properties of a 70 wt.% Ni-30 wt.% Cu alloy. The experimental procedures utilized and the experimental results are presented. Water and air were used as atomizing fluids. The atomizing fluid pressure and the melt pouring temperature were also changed. The following powder characteristics were measured: particle shape and particle size distribution, loss of H2, apparent density and flowability, and particle microstructure. The powder characteristics are correlated with the process parameters. As was expected, water promotes a greater cooling rate than air in the atomizer and particle shape changes were also noted. An increase in the melt pouring temperature and fluid pressure changes the particle size distribution with a decrease in the mean particle size.

Generation of small batch high quality metal powder

Powder Metallurgy, 2014

For the development of a small batch metal atomization system, based on free fall atomization (ffa) and close-coupled atomization (cca), different powder quality features were defined to estimate the influence of the process parameters. Copper-tin alloys were used as feed stock material. Particle size distribution, appearance of satellite particles, particle circularity and the flowability were recorded as criteria of particle quality. Using data obtained in these experiments, main process parameters such as atomization pressure, mass melt flow, and height of the spray chamber as well as the atomizer system have been evaluated with respect to powder quality features. The atomization system was optimized to produce high quality powder with narrow particle distributions ( !",! !",! = 1.6 for ffa) and high circularity with mass melt flows in the range of 100 kg/h using melt volume between 100 and 1000 ml.