The hardness used in plastic molds is generally 480 ~ 520HRC, and it can also be nitrided. Due to the need for heat treatment, the processing is more difficult, so the price of the mold is more expensive. If it needs to be heat treated to a hardness above 40HRC, the mold is generally mechanical Processing is difficult, so the rough machining of the workpiece must be done before heat treatment. The reason is: the water hole, screw hole, and tapping must be done before heat treatment, otherwise it needs to be annealed and redone, then it is time-consuming This type of steel is also commonly used in plastic molds, so there are many brands. The commonly used brands are: ASSAB number: 8407; THYSSEN number is GS344ESR or GS344EFS. (Generally used for fixed parts is GS344ESR, used for moving parts is GS344EFS); Japan ’s Datong Steel DAIDO STEEL HI (most designated by Japanese customers), there are still many brands, because it is not commonly used, so it can not be recorded.
X45 Ni Cr Mo 4 cold-worked steel, AISI 6F7 European number: DIN 1.2767, this kind of steel has a hardness of HB260, which requires heat treatment, and the general hardness is 500 ~ 540HRC. This steel is more commonly used by European customers. This steel has good toughness and polishing effect. Very good, because this steel is not common in South China, so there are not many brands, such as THYSSEN GS767.
X42 Cr 13 (stainless steel), AISI: 420 STAVAX DIN: 1.2083 Factory hardness HB180 ~ 240, heat treatment required, hardness 480 ~ 520HRC, not suitable for nitriding heat treatment (cracks in sharp corners). This steel has good corrosion resistance and polishing effect, so general transparent plastic parts and corrosive rubber materials, such as PVC and fireproof materials, V2, V1, V0 plastics are very suitable for this kind of steel, this steel is also very common Used in plastic molds, so there are many brands, such as ASSAB S-136ESR.
Desheng (THYSSEN) GS083-ESR, GS083 GS083VAR; the use of Desheng should pay attention to, if it is a transparent part, then the fixed and moving mold inserts must be GS083ESR , The polishing effect is better), it is not transparent plastic parts, moving parts generally do not need high finish, you can choose ordinary GS083, because the price of steel is cheaper, and does not affect the quality of the mold, this steel sometimes customers will also require Used as a formwork, because of the anti-rust relationship, it can ensure the smooth flow of water in the cooling pipe to achieve a stable production cycle. This steel type still has many brands and cannot be recorded.
X 36 Cr Mo 17, DIN: 1.2316, AISI 420 STAVAX, factory hardness HB265 ~ 380, depending on the specifications of the steel plant, if it is transparent plastic parts, this steel is generally not used, because when it is polished to a high finish, it is easy because the hardness is not enough There are pits, and it is also easy to have flower marks in beer plastics. It needs to be re-polished frequently, so it is still hardened and tempered by 1.2083 ESR to 480 ~ 520HRC after heat treatment to save a lot of trouble (although this steel is not high in hardness, it is easier to machine cutting , The mold completion cycle is shorter).
