Casting is the literal meaning. The aluminum alloy raw material is heated and melted into a liquid, and then poured into the mold. After cooling and solidification, it becomes a wheel rim. Casting wheels are also divided into low-pressure casting and high-pressure casting. Low pressure casting has low cost and fast production pace, and the original wheelrims are generally low pressure casting. In order to pursue the lightweight effect, the modified rim will pressurize after the aluminum water mold, so that the molecules of the metal after cooling are more closely combined, so as to optimize the mechanical properties and achieve the lightweight effect.
Forging a wheel rim is to directly "pinch" aluminum into a wheel rim, relying on a forging press that can generate tens of millions of tons of forging pressure. Because the forgedrim does not need to undergo the melting-solidification process, the molecular shape does not change, the molecular bond does not break, and in the process of pressure forging, the intermolecular bonding becomes tighter, so the mechanical properties are better than castrims . In theory, monolithic forging can achieve the greatest rigidity-to-weight ratio. This means that for the same weight, the rigidity of the forged rim is higher (that is, commonly known as "hard"); or at another angle, to achieve the same rigidity goal, the forgedrim can be made lighter.
What are the disadvantages of forged wheels besides being expensive?
Because the forged wheel rim is to "pinch" a piece of aluminum alloy into a wheelrim, and the ductility of the aluminum alloy is not very strong, so: 1. The freedom of design of the forged wheel rim is relatively limited; 2. Since it is to "pinch" , In addition to the limited freedom of modeling, excellent raw materials cannot be used, otherwise it will be difficult to form; and it is extremely difficult to "pinch" thick and dense spokes in the forging process, and the transition between the spokes and the "rim" is also difficult to make. Very thick thickness for extreme strength. For these two reasons, the challenge of extremely high hardness still relies on the casting process.