Die casting (note that die casting is not the abbreviation of pressure casting) is a metal casting process characterized by using a mold cavity to apply high pressure to the molten metal. Molds are typically machined from stronger alloys, a process somewhat similar to injection molding.
picture
Sand casting is the use of sand to make casting molds. Sand mold casting requires placing a model of the finished part or a wooden model (pattern) in the sand, then filling the pattern with sand. After unpacking the pattern, the sand forms a mold. In order to take out the model before pouring the metal, the casting mold should be made into two or more parts; during the mold making process, holes and vents for pouring metal into the mold must be left to form a pouring system. After the metal liquid is poured into the mold, it is kept for an appropriate period of time until the metal solidifies. After the parts were removed, the molds were destroyed, so new molds had to be made for each casting.
picture
Investment casting, also known as lost wax casting, includes processes such as wax pressing, wax trimming, tree assembly, dipping, melting wax, casting molten metal and post-processing. Lost wax casting uses wax to make a wax pattern of the part to be cast, and then coats the wax pattern with mud, which is the clay mold. After the clay mold is dried, it is baked into a pottery mold. Once fired, all the wax mold melts and disappears, leaving only the pottery mold. Generally, the pouring port is left when making the mud mold, and then the molten metal is poured into the pouring port. After cooling, the required parts are made.
picture
picture
picture
Die forging is a forging method that uses a die to form a blank on a special die forging equipment to obtain a forging. According to different equipment, die forging is divided into hammer die forging, crank press die forging, flat forging machine die forging, friction press die forging, etc. Roll forging is a plastic forming process in which the material is plastically deformed under the action of a pair of counter-rotating dies to obtain the desired forging or forging blank. It is a special form of forming rolling (longitudinal rolling).
picture
Forging is a processing method that uses forging machinery to exert pressure on metal blanks to cause plastic deformation to obtain forgings with certain mechanical properties, shapes and sizes. It is one of the two major components of forging (forging and stamping). Forging can eliminate defects such as loose as-cast metal produced during the smelting process and optimize the microstructure. At the same time, due to the preservation of complete metal streamlines, the mechanical properties of forgings are generally better than castings of the same material. Important parts in related machinery with high loads and severe working conditions mostly use forgings, except for simple shapes that can be rolled plates, profiles or welded parts.
picture
Rolling, also known as calendering, refers to the process of passing a metal ingot through a pair of rollers to give it a shape. If the temperature of the metal exceeds its recrystallization temperature during rolling, the process is called "hot rolling", otherwise it is called "cold rolling". Calendering is the most commonly used method in metal processing.
picture
The essence of pressure casting is a method of filling the die-casting mold (die-casting mold) cavity with liquid or semi-liquid metal at a high speed under high pressure, and forming and solidifying under pressure to obtain castings.
picture
Low-pressure casting is a casting method in which liquid metal fills the mold and solidifies into a casting under the action of low-pressure gas. Low-pressure casting was initially mainly used for the production of aluminum alloy castings, and later its use was further expanded to produce copper castings, iron castings and steel castings with high melting points.
picture
Centrifugal casting is a technology and method that injects liquid metal into a high-speed rotating casting mold, so that the molten metal fills the mold and forms a casting under the action of centrifugal force. The casting mold used in centrifugal casting, depending on the shape, size and production batch of the casting, can be a non-metallic mold (such as a sand mold, a shell mold or an investment shell mold), a metal mold, or a coating layer or a resin sand layer inside the metal mold. of casting.
picture
picture
Lost foam casting is to bond and combine paraffin wax or foam models similar in size and shape to the castings into model clusters. After brushing with refractory paint and drying, they are buried in dry quartz sand and vibrated to shape. They are poured under negative pressure to vaporize the model. , a new casting method in which liquid metal occupies the position of the model and solidifies and cools to form a casting. Lost foam casting is a new process with nearly no margin and accurate molding. This process does not require mold taking, no parting surface, and no sand core. Therefore, the casting has no flash, burrs, and draft slope, and reduces the number of mold core defects. Dimensional errors caused by combination.
picture
Squeeze casting, also known as liquid die forging, is to inject molten metal or semi-solid alloy directly into an open mold, and then close the mold to generate a filling flow to reach the external shape of the workpiece, and then apply high pressure to make the solidified The metal (shell) undergoes plastic deformation, the unsolidified metal is subjected to isostatic pressure, and high-pressure solidification occurs at the same time. Finally, the method of obtaining a part or blank is the method of direct squeeze casting; there is also indirect squeeze casting, which refers to melting molten metal or semi-solidified metal. A method in which solid alloy is injected into a closed mold cavity through a punch, and high pressure is applied to cause it to crystallize and solidify under pressure, and finally a part or blank is obtained.
picture
Continuous casting is a casting method that uses a penetrating crystallizer to continuously pour liquid metal into one end and continuously pull out the molding material from the other end.
picture
Drawing is a plastic processing method that uses external force to act on the front end of the metal to be drawn, and pulls the metal blank from the die hole smaller than the section of the blank to obtain products of the corresponding shape and size. Since drawing is mostly carried out in a cold state, it is also called cold drawing or cold drawing.
picture
Stamping is a forming processing method that relies on presses and molds to apply external force to plates, strips, pipes and profiles to cause plastic deformation or separation, thereby obtaining workpieces (stamping parts) of the required shape and size.
picture
Metal Injection Molding (MIM) is a new powder metallurgy near-net forming technology derived from the plastic injection molding industry. As we all know, plastic injection molding technology can produce products of various complex shapes at low prices, but plastic The strength of the product is not high. In order to improve its performance, metal or ceramic powder can be added to the plastic to obtain products with higher strength and good wear resistance. In recent years, this idea has evolved to maximize the solid particle content and completely remove the binder and densify the parison during the subsequent sintering process. This new powder metallurgy forming method is called metal injection molding.
picture
Turning processing refers to lathe processing which is a part of mechanical processing. Lathe processing mainly uses turning tools to turn rotating workpieces. Lathes are mainly used to process shafts, discs, sleeves and other workpieces with rotating surfaces. They are the most widely used type of machine tool processing in machinery manufacturing and repair factories. Turning is a method of cutting the workpiece on a lathe by rotating the workpiece relative to the tool. The cutting energy for turning is mainly provided by the workpiece rather than the tool. Turning is the most basic and common cutting processing method and plays a very important role in production. Turning is suitable for processing rotating surfaces. Most workpieces with rotating surfaces can be processed by turning methods, such as internal and external cylindrical surfaces, internal and external conical surfaces, end faces, grooves, threads and rotary forming surfaces. The tools used are mainly turning tools.
picture
picture
Milling milling is to fix the blank and use a high-speed rotating milling cutter to cut out the required shape and features. Traditional milling is mostly used for milling simple shapes/features such as contours and slots. CNC milling machines can process complex shapes and features. The milling and boring machining center can perform three-axis or multi-axis milling and boring processing, and is used for processing molds, inspection tools, molds, thin-walled complex curved surfaces, artificial prostheses, blades, etc. When selecting CNC milling processing content, the advantages and key role of CNC milling machines should be fully utilized.
picture
picture
Planing is a cutting processing method that uses a planer to make horizontal and linear reciprocating motions on the workpiece. It is mainly used for the shape processing of parts. The precision of planing processing is IT9~IT7, and the surface roughness Ra is 6.3~1.6um.
picture
Grinding Grinding refers to a processing method that uses abrasives and abrasive tools to remove excess material from the workpiece. Grinding is one of the most widely used cutting methods.
picture
Selective laser melting In a tank covered with metal powder, a computer controls a high-power carbon dioxide laser to selectively sweep across the surface of the metal powder. Wherever the laser hits, the metal powder on the surface is completely melted and bonded together, while the areas not hit by the laser still remain in the powder state. The entire process needs to be carried out in a sealed chamber filled with inert gas.
picture
Selective laser sintering is an SLS method that uses infrared lasers as energy, and the modeling materials used are mostly powder materials. During processing, the powder is first preheated to a temperature slightly lower than its melting point, and then the powder is smoothed under the action of a scraping stick; the laser beam is selectively Z-sintered according to the layered cross-section information under computer control, and a layer of After completion, the next layer of sintering is performed. After all sintering is completed, the excess powder is removed, and a sintered part can be obtained. At present, mature process materials are wax powder and plastic powder, and the sintering process using metal powder or ceramic powder is still under research.
picture
Metal deposition is somewhat similar to "cream-squeezing" fused deposition, but metal powder is ejected. While the nozzle sprays metal powder materials, it also provides high-power laser and inert gas protection. This will not be limited by the size of the metal powder box, can directly manufacture larger parts, and is also very suitable for repairing partially damaged precision parts.
picture
Roll Forming The roll forming method uses a series of continuous stands to roll stainless steel into complex shapes. The sequence of rollers is designed in such a way that the roller profile of each stand continuously deforms the metal until the desired final shape is obtained. If the shape of the part is complex, up to thirty-six racks can be used, but for parts with simple shapes, three or four racks will suffice.
picture
Die forging refers to a forging method that uses a die to shape a blank on special die forging equipment to obtain forgings. The forgings produced by this method have precise dimensions, small machining allowances, complex structures and high productivity.
picture
Die-cutting is the blanking process. The film formed in the previous process is positioned on the male die of the die-cutting die. The excess material is removed by closing the die, retaining the 3D shape of the product and matching it with the mold cavity.
picture
Die-cutting process - die cutting process, the film panel or circuit is positioned on the bottom plate, the die is fixed on the machine template, and the force provided by the machine's downward pressure is used to control the blade to cut the material. What makes it different from the punching die is that the incision is smoother; at the same time, by adjusting the cutting pressure and depth, it can punch out effects such as indentations and half-breaks. At the same time, the cost of molding is low and the operation is more convenient, safe and fast.
