Preparation methods of 3D printing raw material
2021-03-26
'Additive manufacturing', also known as '3D printing', has become one of the most advanced manufacturing technologies with nearly 30 years of rapid development.'Additive manufacturing' has been widely used in aerospace, automotive, medical and other industries.Refer to the definition given by ASTM:'Additive manufacturing' is the process of connecting materials into objects based on a 3D data model. Compared with the traditional way, 'Additive manufacturing' technology does not require molds, the cycle from design to finished product is shorter, and is not limited by structure and materials.
Due to the above advantages, the 'Additive manufacturing' technology has been praised by some European and American experts as the disruptive technology of the‘ third industrial revolution. Spherical metal powder material is the raw material and consumable of metal additive manufacturing (3D printing) process. Due to the different applications and manufacturing processes requirements, its preparation methods are also different. According to the preparation process, manufacturing methods mainly includes physical and chemical methods and mechanical methods. Current metal powders for additive manufacturing are mainly concentrated in materials such as titanium alloys, high-temperature alloys, cobalt-chromium alloys, high-strength steels, and mold steels.
Plasma Rotating Electrode-comminuting Process (PREP), Plasma atomization PA (Plasma Atomization) andInduction-melting Gas Atomization (GA) are the current main preparation methods for metal powders for additive manufacturing. All these can produce spherical or near-spherical metal powders.
Plasma Rotating Electrode-comminuting Process (PREP) is a spherical powder preparation process developed in Russia. The principle is shown in Figure 1. The metal or alloy is processed into a bar material ,then heated the bar by plasma. At the same time, the bar material rotates at a high speed, and the melted droplets are refined by centrifugal force, then which will solidify and spheroidization transform to powder by the surface tension in an inert gas environment.
Plasma atomization PA (Plasma Atomization) is Canada AP & C's unique metal powder preparation technology. The plasma torch installed symmetrically on the top of the melting chamber forms a high-temperature plasma focus, the temperature can even be as high as 10000K, the special feeding device sends the metal wire into the plasma focus, the raw material is quickly melted or vaporized, and the plasma is impacted at high speed Dispersed and atomized into ultra-fine droplets or aerosols, in the process of flying deposition in the atomizing tower, heat exchange cooling and solidification into ultra-fine powder with cooling argon gas passing into the atomizing tower, the schematic diagram of PA equipment is shown in Figure 2. The metal powder prepared by PA method is nearly regular spherica, the overall particle size of the powder is fine.
At present, the common techniques for gas atomization preparation of metal powder materials for additive manufacturing include Vacuum Induction-melting Gas Atomization (VIGA) and Electrode Induction-melting inert Gas Atomization (EIGA), the principles of the two methods are shown in Figure 3 and Figure 4. Among them, the VIGA method is mainly suitable for the production of iron-based alloys, nickel-based alloys, cobalt-based alloys, aluminum-based alloys, copper-based alloys and other powders, while the EIGA method is mainly applied to active metals and their alloys, intermetallic compounds, refractory metals Preparation of powder materials such as titanium and titanium alloys, titanium aluminum intermetallic compounds.
Now our company will build a production line product the metal powder is used for 3D printing in the method of EIGA. Compared with other methods, EIGA method has the advantages of material saving, flexible production and more fine powder output in preparing active metal powder, so it is suitable for the production and preparation of titanium alloy powder for SLM process.
Our company is willing and have ability to provide all kinds of high quality metal powder used for 3D printing for you. If you have demand of these products, please contact us.
（Edit: Xinuo Titanium）
