Hot Isostatic Pressing Process And Application Of TC4 Titanium Alloy Powder
Powder is the prerequisite and basis for the preparation of TC4 titanium alloy powder metallurgy components, and the physical properties of powder play a very important role in the performance of powder hot isostatic pressing parts. The commonly used pre-alloy powder preparation processes of TC4 titanium alloy powder mainly include cold-wall crucible vacuum induction melting and atomization, electrode induction melting and atomization (EIGA) and plasma rotating electrode atomization. Among them, the powder prepared by EIGA method is popular due to its excellent comprehensive cost performance.
Electrode induction melting gas atomization (EIGA)
TC4 titanium alloy is made into electrode rod. The electrode rod is heated and melted by induction coil to form a small liquid flow. The liquid drop is broken by the spray plate under the action of high-speed inert gas flow and quickly condensed into powder. The process is in the mode of no crucible and no guide tube, and the prepared powder has high purity.
Hot isostatic pressing (HIP) process is a technology that uses inert gas as the force transmission medium and protective atmosphere to obtain highly densified parts in a controlled high temperature (below 2000 ℃) and high pressure (100~200Mpa) closed container after applying isotropic static pressure to the surface of the package or parts placed in it. The HIP process has been widely used in many fields, such as the sintering preparation and post-forming treatment of cemented carbide such as TiC The densification of large casting products, the densification of target materials and printing pieces, the elimination of internal defects of titanium molybdenum and other superalloys, and the diffusion bonding of difficult-to-weld materials.
Hot isostatic pressing principle
Hot isostatic pressing internal pore removal defect
The powder hot isostatic pressing (HIP) process combines the near-net forming characteristics of powder with the excellent material performance characteristics of hot isostatic pressing. It is a method that can achieve the densification and near-net forming effects at the same time. Its advantages include: high material density, close to 100% relative density, good microstructure, high purity, fine grain, uniform structure, small internal stress and other properties can fully reach or exceed the level of forgings.
Hot isostatic pressing process route of TC4 titanium alloy powder
The TC4 titanium alloy powder hot isostatic pressing process can eliminate defects, effectively improve the mechanical properties of titanium alloy parts, meet the high requirements of high-end equipment, reduce the cost of titanium alloy, improve the production efficiency and utilization rate of titanium alloy, and solve the problems of titanium alloy technology from two aspects.
Application of hot isostatic pressing process for TC4 titanium alloy powder
In 1955, the first HIP equipment was successfully developed in the United States, marking the birth of HIP technology. The United States has vigorously developed the technology of powder titanium alloy in aerospace engineering and military fields, with advantages, such as F14 engine nacelle frame and fuselage support, F-15 fighter TC4 titanium alloy keel joint, F18 engine fixed support, etc. The aero-engine compressor housing prepared by the UK's R-R engine company and the University of Birmingham through the combination of computer simulation and HIP near-net forming technology is a large powder titanium alloy HIP near-net forming aviation structural part in the current public report.
High-performance Ti-6Al-4V titanium alloy aero-engine compressor housing produced by R-R company's HIP near-net forming technology,
At present, domestic scientific research institutes have carried out a lot of work and developed a number of powder titanium alloy components with excellent performance, many of which have been applied to aerospace and military industry, such as aero-engine, spacecraft, hydrogen pump impeller, thin-walled cabin, air rudder frame, missile tail, tank, turbine disk, submarine periscope cylinder, etc., especially on the basis of the successful flight test of C919 aircraft, Powder titanium alloy will have greater development in the domestic aviation field. The Aerospace Materials and Technology Research Institute is the first unit in China to carry out near-net-formed powder titanium hot isostatic pressing. The products developed include aerospace components of various brands (such as TC4, TC11, TA7, TA15), such as brocade plate framework structural parts, barrel parts, horizontal wing framework, impeller, etc. Powder titanium alloy products developed by Aerospace Materials and Technology Research Institute
In the civil market, with the rapid growth of the market demand for 3D printers, the demand for titanium alloy substrate for printing is also gradually increasing. The use of TC4 titanium alloy powder hot isostatic pressing to form titanium substrate also has a strong potential market
