Are you curious about how metal parts are formed and shaped into the products we use every day? Look no further because this blog post will take you on a journey through the various metal forming technologies used in industry today.
From die-casting to milling, we’ll explore the intricacies of each method and the unique advantages they offer. Whether you’re a seasoned engineer or simply interested in the manufacturing process, this article will provide a comprehensive overview of metal forming technology.
So, buckle up and get ready to learn about the fascinating world of metal forming!
The process involves using a mold cavity to apply high pressure to molten metal. The molds are typically made of stronger alloys and are similar to those used in injection molding.
Sand mold casting involves creating a mold using sand. The finished product or wooden model is placed in sand and the sand is filled around the shape of the model. To remove the model before casting metal, the mold is made in two or more parts. The process includes creating holes and vent holes for casting metal and a pouring system. After casting the metal, it remains in place until it solidifies. The mold is destroyed after the parts are taken out, so new molds must be made for each casting piece.
Lost wax casting, also known as investment casting, involves the following processes: wax injection, wax polishing, dipping, dewaxing, casting liquid metal, and post-treatment.
Lost wax casting starts with a wax mold of the desired part, which is then coated with a loam mold. The loam mold is then baked to form a ceramic mold. The wax mold melts away during the baking process, leaving only the ceramic mold.
A sprue gate is left in the loam mold, through which the molten metal is poured into the mold. After cooling, the final part is produced.
It is the forging method by using mold on special die forging equipment for blank forming. 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 the plastic forming process of the required forging or forging stock for the material under the action of a pair of reverse rotating dies. It is a special form of forming rolling (longitudinal rolling).
Forging is a fabrication method that involves the use of a forging press to apply pressure on a metal billet, causing plastic deformation and resulting in improved mechanical properties, shape, and size.
Forging is one of the two components of stamping, the other being stamping.
The microstructure is optimized through forging, eliminating defects such as loose casting in the smelting process. This, combined with the preservation of the complete metal streamline, results in forgings with mechanical properties that are generally superior to those of cast parts made of the same material.
Parts subjected to heavy loads and severe working conditions in related machinery are mostly made of forgings, with the exception of simple forms such as rolled sheets, profiles, or welding parts.
Calendering, also known as rolling, is the process of forming a metal ingot through the use of a pair of rollers.
If the temperature of the metal exceeds its recrystallization temperature, the process is referred to as hot rolling. If not, it is referred to as cold rolling.
Rolling is the most commonly used method for metal processing.
The essence of pressure casting is to fill the die casting mold cavity with liquid or semi-liquid metal at high speed under the effect of high pressure, and to form and solidify the casting parts under pressure.
The casting method involves filling a casting mold with liquid metal, which is then solidified under the action of low-pressure gas.
Low-pressure casting was originally used mainly for the production of aluminum alloy castings, but has since expanded its use to include the production of castings made of high melting point materials such as copper, iron, and steel.
In centrifugal casting, liquid metal is injected into a high-speed rotating casting mold, where it is filled and formed into casting parts under the action of centrifugal force.
The type of casting mold used in centrifugal casting can vary depending on the shape, size, and volume of production. It can be made of non-metallic materials such as sand, shell, or melting mold shell, metal, or a coating layer or resin sand layer on a metal mold.
Lost Foam Casting
Lost foam casting combines a foam model similar in size to the desired casting parts with paraffin wax to form a model cluster. After painting and drying, the cluster is buried in dry quartz sand and shaped through vibration. The mold is then cast under negative pressure, causing the model to vaporize and the liquid metal to occupy its position, solidifying to form the casting parts.
Lost foam casting is a relatively new process that offers nearly infinite precision.
The process requires no die, no parting surface, or sand core, resulting in castings without flying edges, burrs, or draft angles. This also reduces the size errors caused by the combination of model and core.
Liquid die forging, also known as direct extrusion casting, involves injecting molten metal or semi-solid alloy directly into an exposed mold. The mold is then closed to produce filling flow and shape the outer contours of the piece. High pressure is then applied to create plastic deformation in the solidified metal (shell). The unsolidified metal is subjected to static pressure, solidifying under the influence of high pressure to produce the finished product or blank.
There is also indirect extrusion casting, which involves injecting molten metal or semi-solid alloy into a sealed mold cavity through a punch. High pressure is then applied to solidify the metal under pressure and produce the final workpiece or blank.
Continuous casting is a casting method where liquid metal is poured continuously at one end into a crystallizer, and the molding material is continuously pulled from the other end.
Cold drawing, also known as cold drawing, is a plastic processing method that applies external force to the front end of a metal billet, resulting in the billet being pulled out from the die hole of the blank section to attain the desired product shape and size.
The process is called cold drawing because it is performed in a cold state.
Stamping is the process of forming workpieces (stamping parts) into the desired shape and size by applying external force to plates, strips, pipes, and profiles. This is achieved through plastic deformation or separation using a pressing machine and die.
Metal Injection Molding
Metal injection molding (MIM) is a new type of powder metallurgy near-net forming technology that has been introduced from the plastic injection molding industry.
It is well known that plastic injection molding is a cheap method for producing a wide range of complex shapes, but the resulting plastic is not very strong. To improve its performance, metal or ceramic powders can be added to the plastic, resulting in high-strength and wear-resistant products.
Recently, the idea has evolved to maximize the content of solid particles, with the binder being completely removed during the subsequent sintering process, resulting in densified forming.
This new powder metallurgy method is known as metal injection molding.
Lathe processing is a part of machining. Lathe machining primarily involves the use of a lathe tool to turn the workpiece through rotation.
The lathe is mainly used for machining shafts, discs, sleeves, and other workpieces with rotating surfaces, and is the most widely used machine tool in machine manufacturing and repair shops.
Turning machining involves cutting the workpiece by using the rotation of the workpiece relative to the tool on the lathe. The cutting energy is mainly provided by the workpiece rather than the cutter, making turning the most basic and common cutting processing method, with a significant position in production.
Turning is suitable for machining revolving surfaces, and most workpieces with rotating surfaces can be machined by turning, such as inner and outer cylinders, inner and outer cone faces, end faces, grooves, threads, and rotary forming surfaces. The main tool used is the lathe tool.
Milling involves fixing the blank and using a high-speed milling cutter to move across the surface of the blank and cut out the desired shape and features.
Traditional milling is used for milling contours and grooves.
NC (numerically controlled) milling machines are capable of processing complex shapes and features.
Milling and boring machining centers can be used for three-axis or multi-axis milling and boring processing, and are mainly used for fabrication molds, inspection tools, plates, thin-wall complex curved surfaces, artificial prostheses, blades, and so on.
When selecting an NC milling machine, it is important to fully utilize its advantages and key functions.
The machining method involves cutting the workpiece using a planer tool in a horizontal, linear reciprocating motion. It is primarily used for contour machining of parts and has a precision of IT9 to IT7, with a surface roughness of 6.3 to 1.6um.
Grinding refers to the process of removing excess material from a workpiece using abrasive materials and tools. Grinding is a widely used machining method.
Selective Laser Melting
In a tank filled with metal powders, a high-power carbon dioxide laser controlled by a computer selectively scans the surface of the metal. Where the laser passes, the surface of the metal is completely fused together, while the surrounding powder remains in its original state. The process occurs within a capsule filled with an inert gas.
Selective Laser Sintering
The molding materials processed using infrared lasers are primarily powder-based. The process involves preheating the powder to a temperature just below its melting point, then smoothing it using a cupping stick. The laser selectively sinters the powder according to layered section information controlled by a computer. Once a layer is complete, the next layer is sintered. After sintering is finished, any excess powder is removed, yielding a sintered part. Currently, the most mature process materials are wax and plastic powders, while sintering with metal and ceramic powders is still under investigation.
This process is similar to “squeeze casting,” but instead uses metal powder that is ejected. The nozzle also provides high-powered laser and inert gas protection during the extrusion of metal powder. This method is not limited by the size of the metal powder container and can produce larger components directly. It is also suitable for repairing locally damaged precision parts.
The roll forming method involves using a series of continuous frames to shape stainless steel into complex forms.
The rolls are arranged in a specific order to continuously deform the metal until the desired final shape is achieved.
For complex shapes, up to 36 frames may be required, while simple shapes can be achieved with just 3-4 frames.
The die is utilized in specialized die forging equipment to form a blank and produce forgings.
The forgings produced through this process are characterized by their precision in size, minimal machining allowance, complex structure, and high productivity.
This technology falls under the category of blanking.
The preformed film is placed on the male die of the punch press, which uses a compound die to remove excess material and preserve the 3D shape of the product, ensuring a proper fit with the mold cavity.
This technology pertains to blanking using a cutting die.
The thin film panel or line is positioned on the base plate and the die is secured to the machine template mold. The machine then uses its power to control the blade and cut off the material.
What sets it apart from punching die technology is the smoother cut it produces. Additionally, it allows for adjustments to the cutting pressure to produce indentations, half-cut effects, and other desired outcomes.
This technology also offers the benefits of low-cost mold production, making it more convenient, safe, and fast.