Casting you don’t know-the difference between 9 casting techniques

Die casting (die casting is an abbreviation of pressure casting) is a metal casting process that uses a mold cavity to apply high pressure to molten metal. Molds are usually made of higher-strength alloys. This process is somewhat similar to injection molding.

Sand casting is the use of sand to make molds, commonly known as sand casting. Sand casting requires putting a finished part model or a wooden model (pattern) in the sand, and then filling it with sand on the weekend of the pattern. After the pattern is taken out of the box, the sand forms a mold. In order to take out the model before casting the metal, the casting mold should be made into two or more parts; during the manufacturing process of the casting mold, holes and vent holes for casting the metal into the casting mold must be reserved to synthesize the casting system. After pouring the metal liquid into the mold, keep it for an appropriate time until the metal solidifies. After the parts were taken out, the mold was destroyed, so a new mold must be made for each casting.

Investment casting is also called lost wax casting, precision casting, including pressing wax, wax repairing, tree formation, dipping, melting wax, casting molten metal, and post-treatment. Lost wax casting is to use wax to make a wax mold of the part to be cast, and then coat the wax mold with mud, which is a mud mold. After the clay molds are dried, they are baked into pottery molds. Once baked, the wax molds are all melted and lost, leaving only the pottery molds. Generally, a pouring port is left when making a mud mold, and then molten metal is poured from the pouring port. After cooling, the required parts are made.

The essence of pressure casting is to fill the cavity of a die-casting mold (die-casting mold) with liquid or semi-liquid metal at a higher speed under high pressure, and form and solidify under pressure to obtain castings.

Low-pressure casting A casting method in which liquid metal is filled into a mold and solidified 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 expanded its use to produce copper castings, iron castings and steel castings with high melting points.

Centrifugal casting is a technology and method that injects liquid metal into a high-speed rotating 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, according to the shape, size and production batch of the casting, can choose non-metallic type (such as sand mold, shell mold or investment shell mold), metal mold or coating layer or resin sand layer in the metal mold Of casting.

Lost foam casting is to combine paraffin wax or foam models similar to the casting size and shape into model clusters. After brushing with refractory coating and drying, it is buried in dry quartz sand for vibration modeling, poured under negative pressure to gasify the model , Liquid metal occupies the position of the model, and forms a new casting method after solidification and cooling. Lost foam casting is a new process with nearly no margin and precise molding. This process does not require mold taking, no parting surface, no sand core, so the casting has no flash, burr and draft angle, and reduces the core Size error caused by combination.

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 outer shape of the part, and then apply high pressure to make the solidified The metal (shell) is plastically deformed, the unsolidified metal is subjected to isostatic pressure and high-pressure solidification occurs at the same time, and the final product or blank is obtained. The solid alloy is injected into a closed mold cavity through a punch, and high pressure is applied to crystallize and solidify under pressure to form a final product or blank.

Continuous casting is a casting method in which liquid metal is continuously poured at one end using a through mold, and the molding material is continuously drawn out from the other end.


Post time: Sep-11-2020