(PDF) Powder Metallurgy Processes and Making Metal Powder

<P><p><div><p>which has undergone many processes. Powder metallurgy, which is an advanced production method, is a production method that allows the production of all technological parts, using very small parts, can be applied very quickly, economically advantageous and facilitates the production of even shaped parts. Powder Metallurg y is widely used today and is a good alternative to its old methods. The annual turnover in th e powder metallurgy in the European market exceeds six billion euros, even the worldwid e production of metal po wder is more than one million tons. Apart from the casting method, which can only be applied on low hot melt metals, the powder metallurgy method is applicable to almost all materials. Most of product which produced by applying powder metallurgy method cannot be produced by choice of raw material an d continues until it becomes the production of v e ry complex products. The first stage starts with powder selection. The selected powder is selected according to the requirements of the part to be produced. The properties of the powder are important for the properties of the part to b e produced. Production with powder metallurgy also has a flow char t that progresses at certain stages. Fig ure 1 shows the stages of production with The raw powder is mixed with some allo y elements and by adding lubricant or some s pecial additives. Mixing is done until a homogeneous mixture is obtained . This composition is of great importance in determining the The aim of this stage is to put the obtained powder mixture into the molds and bring them to the required shape and size. Shaping is carried out with sufficien t density and This process step includes the par ts are heated in a protective atmosphere with a temperatu re below the meltin temperature. As a result of the process, the porous structure in the piece disappears and it gains strength and stiffness growth are seen in the structure of the powder particles. The parts that appear after sintering become close to the final state. These parts, which are mostly formed after sintering, are ready to be finished without the n eed for secondary processing. However, in some cases, secondary operations may be required for these parts. These secondary operations are carried out when necessary, even if they are not economically advantageous. The reason for performing and improvements to the parts. e parts coming out of sintering can be calibrated to their properties such as surface sen sitivity, measurement precision, and density by using a different mold than The pores in this part can be filled with a metal, alloy, or oil depending on t he need. Sinter bushes produced as oil impregnation can be given as an example. [ After the pores on the surface of the part are closed, coating is performed. The surfaces of the parts can be ste at 600 degrees. This process provides an improvement in the properties of the part such as abrasion,</p><img src="//img.yfisher.com/1629249179850.jpg" style="margin:10px auto"><p><b>1. What are the most potent non-nuclear explosives?</b></p><p>fielded: HMX based, pressed polymer bonded explosives with 5 % of binder (shattering) or HMX based PBX, pressed with 30 % of Al and 5 % binder (shockwave power), thermobaricsynthetized: HNIW, TKX-50 and other, mostly 5-membered nitrogen rich heterocycle based explosivesin sillico (in computer models) polynitrogen and poly -N2O compounds with N60 being the most powerful that I know ofThe differences between shockwave power (blast size) aren't that big.. you get like 2 - 5 as much as TNT, even DPX-5 does only about 180 % TNT in the far field (HMX, Al, binder).. and N60/polynitrogens won't be much more powerful.... maybe 5 (i dunno the exact number)however, the differences in brisance, i.e. shattering steel and penetrating armor will be extremely large with N60 being about 10 better in this role than TNTAs far as easily made homemade explosives go, melt cast ETN/PETN (being close to best fieldedpressed HMX type explosives, 310 vs 360 kbar) and melt cast ETN/magenesium-aluminium alloy powder 55:45 that is completely comparable to DPX-5 (HMX/AL, binder)Brisancce:TNT - about 180 kbarSemtex - 220 kbarC4 - 250 kbarmelt cast ETN/PETN - 310 kbarpressed HMX PBX 5 % binder - 360 kbarHNIW pressed, free of binder - 410 kbarN60 - 2000 kbar IIRCenergy/explosion size/shockwave:TNT - 4 MJ/kgSemtex or C4 - 5 MJ/kgDPX-5 (HMX, Al, binder) or melt cast ETN/magnesium-aluminium - 8 MJ/kg (explosives with high % of <a href="https://od7ctc3g.lifisher.com/ai-article/pdf-powder-metallurgy-processes-and-making-metal-powder.html">metal powder</a> all called thermobaric explosives)some polynitrogen compounds like N60 - up to 23 MJ/kgWhat are the most potent non-nuclear explosives?</p><p><b>2. Laser welding, additive manufacturing enable equipment refurbishments with less effort</b></p><p>Pretoria, South Africa - The National Laser Centre of the Council for Scientific and Industrial Research (CSIR) has developed laser-based refurbishment techniques, including laser welding and additive manufacturing, that have made it possible to refurbish equipment that would otherwise have had to be scrapped or previously required much more effort, according to Herman Burger, the Centre's research group leader for laser material processing. Leaking water tanks at the Koeberg nuclear power plant in the Western Cape of South Africa were refurbished with laser cladding technology, at far less than the estimated R1bn replacement cost. Laser surface welding technology has increased service life and lowered the ownership costs of continuous caster rolls at the ArcelorMittal factory in Vanderbijlpark, South Africa. CSIR's capability ensures that expensive repairs performed overseas in the past are now done in the country. "Both MAN Diesel and Turbo and Tupperware used to send components to Germany and Belgium, respectively, when laser cladding was required," Burger says. "Large, heavy components were shipped to the other side of the world to have a few kilograms of weld metal deposited by laser. It was extremely wasteful in terms of time, transport costs, and European labor rates. Now, it is done here." MAN Diesel and Turbo projects and sales manager Christo du Plooy says rotating parts on machinery would traditionally have been repaired with metal spraying or submerged arc welding. The cost of laser refurbishment is high, but he believes that as the technology matures, its cost-effectiveness will increase. The National Laser Centre also welds rocket motor casings for Denel Munition. Laser welding is used to produce cyclotron radiation targets for the production of radio isotopes for iThemba Labs. Lasers extend the service life of industrial components by improving oxidation and corrosion resistance, and increasing resistance to abrasive wear-leading to massive savings. Laser cladding is a weld overlay process in which a coating is placed on a worn metal surface-restoring and sometimes improving components. A high-power laser generates a small puddle of molten metal, called a weld pool, on the surface in need of repair. <a href="https://od7ctc3g.lifisher.com/ai-article/pdf-powder-metallurgy-processes-and-making-metal-powder.html">metal powder</a> is then injected into the pool and when the laser beam and the powder mix, a new layer of metal is created and bonded to the old metal, creating robust adhesion. Last year CSIR engineers designed a mobile system based on this technology, used to repair high-value components on site. The other application of laser surface modification is laser hardening. A laser beam rapidly heats the surface layer of a carbon steel component. The new layer created hardens after rapid cooling. The CSIR has developed laser hardening processes for the armaments industries, Daimler Chrysler, and Bell Equipment. Lasers are used for additive manufacturing, similar to 3D printing. Laser beams fuse <a href="https://od7ctc3g.lifisher.com/ai-article/pdf-powder-metallurgy-processes-and-making-metal-powder.html">metal powder</a>s together, layer by layer, to produce a fully functional part from computer-aided design data. "Laser additive manufacturing is particularly advantageous where high-value components are manufactured from expensive and difficult-to-machine materials," says Burger. "Arguably, the biggest advantage of additive manufacturing is that it allows component design to be optimised for functionality rather than manufacturability." The CSIR is in partnership with aeronautical engineering company Aerosud, which is focusing on the development of technologies that will enable high-speed production of large components. The project is funded by the Department of Science and Technology. "We already use 3D printing for the manufacture of aircraft parts in plastics, such as air conditioning ducts. However, laser additive manufacture is a totally new technology for us. We are now developing a first pilot plant, so the technology will only be mature enough for production in three to four years," says Aerosud MD Paul Potgieter.</p><img src="//img.yfisher.com/1629249176702.jpg" style="margin:10px auto"><p><b>3. At the current technological advancement rate, how quickly would we be able to 3D print weapons on the battlefield?</b></p><p>I am going to go the other way and say it would take something like 20 years for viable 3d printing on the battlefield. Now these wo not be portable 3d printers individual soldiers carry, but much larger bulkier 3d printers which would be stationed nearby and manned by a team and maybe placed on a moving vehicle.Having a quick search, I would imagine something similar to the powder bed fusion method, where multiple heads deposit a layer of <a href="https://od7ctc3g.lifisher.com/ai-article/pdf-powder-metallurgy-processes-and-making-metal-powder.html">metal powder</a> and a high power laser melts the powder to form the metal structure. Multiplying the number of heads that deposit <a href="https://od7ctc3g.lifisher.com/ai-article/pdf-powder-metallurgy-processes-and-making-metal-powder.html">metal powder</a> and the laser increases printing speed.This would be much better than your traditional 3d printing where the printer head has to deposit the material. You can print the entire layer much faster, and you can start printing the next layer while the previous layer is still printing. The speed limitations would come from the laying down the <a href="https://od7ctc3g.lifisher.com/ai-article/pdf-powder-metallurgy-processes-and-making-metal-powder.html">metal powder</a>, and the time taken for the melted metal to become stable enough for the next layer of powder to sit on it and retain the shape you want.You would also 3d print multiple parts together. Utilizing the whole printing bed rather than a single section, since the printer head always has to traverse the entire bed each time you make an additional layer.</p></div></P><P></p></P>