Metal powder is porous materials widely used in many things such as lightweight structural materials, high temperature filters, membranes, etc. The biggest market maybe is the smoke filtration device of diesel engine. Germany's Fraunhofer Institute has developed a metal hollow sphere preparation technique, the polymer substrate coated metal powder slurry, and then de-coating polymer matrix and binder, and finally sintered into a variety of metal sphere with a hollow structure . 1mm diameter sphere bundle to 8mm. The preparation of the density of steel hollow ball only 0.3g/cm3.
Nanocrystalline carbide and gradient structure of the two key directions. Nanocrystalline materials, including grain growth control and nano-powder preparation. Gradient structure alloys, including the relationship between technology and structure. The gradient structure of nanocrystals and might be a good combination of direction, to achieve a more micro-level performance adjustable. Cemented carbide, high hardness, machinability is poor, manganese powder so a small complex shapes prepared by injection molding parts is a trend, but the commercialization of technology maturity are still subject to the control. Carbide other aspects of the work day at home, including rare earth elements and alloys, fracture toughness and reliability characterization.
Automotive lightweight aluminum, magnesium, titanium and other light metal material provides a broad application prospects. Aluminum powder can be applied in the car on the site very much, but the Al-Si alloy due to the high specific strength, high stiffness, low thermal expansion coefficient and good wear resistance, boron powder it is possible in the first large-scale application in the oil pump gear. From the industrial point of view, the preparation process of powder metallurgy aluminum alloy optimization studies are more important. Another research focus is aluminum composite materials, including traditional Al / SiC, Al / C, Al / BN, Al / Ti (C, N) and the emerging carbon nanotube enhanced aluminum. High-strength aluminum alloy powder is closely related with the rapid solidification technology. By composition design in aluminum matrix by adding the line into components of intermetallic compounds can be prepared by high strength, high toughness, high thermal stability of both the aluminum. The room temperature strength than the material 600Mpa, more than 10% elongation at 400 ℃ have good thermal stability, forged aluminum alloy fatigue limit is 2 times.
Smaller the density of magnesium alloy and its application prospects may be better, but still in the research state. Prepared by rapid solidification method using high-performance powder is an important means of magnesium alloy. Present the technology in security has been no significant problems, silicon powder the performance of the material prepared is much higher than cast alloys.
Titanium alloys in automotive applications is mainly the cost problem, and titanium alloy powders The main obstacle to high-performance low-cost titanium powder. UK QinetiQ Ltd has developed a technology store oxygen (EDO), can be mass production of titanium powder. The technology and the traditional sponge titanium hydride dehydrogenation process as raw material is completely different. It is similar to the molten salt electrolysis method, using TiO2 as cathode, graphite as the anode in the electrolysis process of TiO2 anode migration, and consumption of carbon anode to form CO, titanium powder obtained in the cathode. The oxygen content of titanium powder 0.035% to 0.4%, respectively. This technology can also be easily used in preparation of titanium alloy powder. Because of the impurities in the atmosphere and the sensitivity of titanium alloy powder sintering process is difficult, usually to hot isostatic pressing or subsequent thermal processing. Eutectic formed by adding a group element and rare earth elements can significantly improve the density of sintered titanium powder, the mechanical properties of titanium can be forged to achieve the level. This series will greatly promote the critical titanium components in the automotive drive applications. Source:http://www.mhcmp.com