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Motor Frame Design
Published in Wei Tong, Mechanical Design and Manufacturing of Electric Motors, 2022
Like regular extrusion processes, the impact extrusion process is a type of specialty cold forming process. In an extrusion process, a metal blank is placed inside a die. A punch impacts the metal blank with an extremely high force to make it to extrude in one of the three matters (Figure 5.12): (a) in a forward impact extrusion, the punch pushes the metal through the orifice of the die, in the same direction of the applied force; (b) in a backward impact extrusion, the metal is forced to flow backward around the punch through an opening between the die and the punch, in the opposite direction of the applied force; and (c) in a combined impact extrusion, the metal flows in both forward and backward directions. The impact extrusion process is best suited for the fabrication of small motor housing with materials such as aluminum.
The mechanical shaping of metal
Published in William Bolton, R.A. Higgins, Materials for Engineers and Technicians, 2020
Disposable tubes in lead, tin and aluminium are used as containers for a wide range of substances, e.g. shaving cream, toothpaste, medicines and adhesives, though in recent years thermoplastic materials have replaced aluminium in many such containers. Impact-extrusion is also used for the production of many other articles, principally in aluminium, e.g. canisters and capsules for food, medical products and photographic film, and shielding cans for radio components.
Metal Forming
Published in Sherif D. El Wakil, Processes and Design for Manufacturing, 2019
Impact extrusion involves striking a cold slug of soft metal (like aluminum) that is held in a shallow die cavity with a rapidly moving punch, thus causing the metal to flow plastically around the punch or through the die opening. The slug itself is a closely controlled volume of metal that is lubricated and located in the die cavity. The press is then activated, and the high-speed punch strikes the slug. A finished impacted product is extruded with each stroke of the press. These products are not necessarily cylindrical with a circular cross section. In fact, the range of shapes possible is very broad, including even irregular symmetrical shapes. There are three types of the impact extrusion processes: forward, reverse, and combination (the names referring to the direction of motion of the deforming metal relative to that of the punch).
Failure mechanism and impact resistance of all GFRP Miura-ori with platforms sandwich structure under low-velocity impact experiments
Published in Mechanics of Advanced Materials and Structures, 2023
Figure 14 shows the damage morphologies of the impact of different energies at the base with a hemispherical impactor. The impactor penetrates the upper panel and causes damage to the core wall directly in the test HI-BASE-15J, resulting in cross cracks on the upper panel. Compared impact at the node with the same energy, the failure area of the upper panel at the base is more extensive, the damage range of the panel of 30 J is similar with that of the 15 J because adjacent Miura-ori prevents damage expansion and excessive bending of the upper skin. The left wall is subjected to impact extrusion and produces slight buckling, which is caused by the Miura-ori configuration and is more prone to damage at the concave side of the Z-line corner [40]. When the energy increases to 100 J, the core is unbonded with the lower panel, and an obvious crack appears between the platform and the right wall. The lower panel shows the same protruding rectangular pyramid at the node.
Experimental investigation on ultrasonic surface rolling of Inconel 690TT
Published in Materials and Manufacturing Processes, 2021
Junbiao Liu, Xuehui Zhang, Ziyi Cui, Jiatian Yu, Jiang Liu, Yangjun Zou, Tongxiang Liang
Figure 3 is the SEM image of Inconel 690TT surface morphology of RR-1 to RR-4 specimens. It could be observed that the surface of RR-1 sample still retained the surface morphology characteristics of the untreated sample, and the scratch direction was dense and parallel but 0.2 mm USRP was smooth and flat. It indicated that the USRP treatment could significantly smooth the surface morphology. And in USRP process, the WC-Co ball was usually applied to the surface of the sample with high-frequency vibration, resulting in serious surface plastic deformation due to impact extrusion, and plastic flow would affect the flattened material surface.[22] The RR-3 and RR-4 mm specimens treated with USRP formed peaks and cracks due to severe deformation. The results show that the surface topography would deteriorate under the condition of full-coverage treatment when RR exceeded a certain value.
Study on the preparation and properties of CaCO3 ultrafine powder derived from waste eggshell
Published in Environmental Technology, 2022
Yue Qiu, Yuyang Hou, Shiyu Zhang, Leilei Jin, Jun Zhou, Jishuang Chen
Ball mill is an important grinding equipment widely used in metallurgy, chemical, building and other industries of fine grinding process [19]. In the process of ball milling, a series of changes in physical and chemical properties of CaCO3 particles, such as particle size reduction, surface wettability enhancement, solubility increase and chemical activity enhancement, were obtained through the impact, extrusion and shear of the ball milling medium and CaCO3 [20]. The particle size and specific surface area of CaCO3 can be changed by ball milling. Continuous use of ball milling does not make the size of CaCO3 continuously smaller. In the process of ball milling, the crystal type of CaCO3 is changed, which is usually transformed into the most thermodynamically stable calcite, and aragonite can also be transformed under certain conditions [21]. Different crystalline structures of CaCO3, such as needle-like CaCO3, chain-like CaCO3, spherical CaCO3 and three-dimensional CaCO3, can be produced by ball milling with different crystal control agents. These different crystalline forms of CaCO3 can be widely used in plastics, coatings, rubber and paper industry [22,23]. Therefore, it is a good material reinforcement material. Ball mill has the advantages of simple structure and high grinding efficiency. However, it also has the disadvantages of high energy consumption, which accounts for more than 30% of the total cost [24,25], and low machining efficiency. Therefore, the best operation parameters in the process of using ball mill must be explored to reduce energy consumption and improve production efficiency.