Surface treatment of plastic mold steel

Surface treatment method: 1. Nitriding treatment 2. Heat treatment
　　 (1) C45 W medium carbon steel
　American standard number: AISI 1050 ~ 1055; Japanese standard number: S50C~ S55C German standard number: 1.1730　. China Carbon Steel or 45# steel is called Ace Steel in Hong Kong. The hardness of this steel is: HB170 ~ HB220, which is cheap and easy to process. It is used as a mold base, top pillar, and some unimportant parts on the market. The general standard formwork adopts this kind of steel;
　　 (two) 40 CrMn Mo 7 pre-hardened plastic mold steel   plastic die steel
　American, Japan, Singapore, Hong Kong, China standard code: AISI P20, Germany and some European countries code: DIN: 1.2311, 1.2378, 1.2312. This kind of steel is pre-hardened steel, which is generally not suitable for heat treatment, but it can be nitrided. The hardness of this steel grade is also very different. From 28 to 40 HRC depending on the standard of the steel plant, because it has been pre-hardened, Mechanical cutting is not too difficult, so it is very suitable to make inserts for some medium and low price molds. Some mold bases for mass production also use this steel (some customers specify that this steel is used as a mold base). The advantage is that the hardness is more than medium. Carbon steel is higher and its deformation is more stable than medium carbon steel. Because P20 is widely used in plastic molds, there are many brands. Among them, the more common brands in southern China are: ASSAB, two from Sweden Different hardness, 718S HB290~HB330 (33~34HRC), 718H HB330~HB370 (34~38HRC). Datong Steel Plant, made in Japan: NAK 80 (hardness 40HRC+20) and NAK55 (hardness 40HRC+20). Under normal circumstances, NAK 80 is used for fixed mold inserts, and NAK55 is used for movable mold inserts. Note that NAK55 cannot be used directly. EDM skin texture, according to the steel agent's explanation, is related to sulfur, so there are stripes after EDM; Desheng Steel Works THYSSEN, made in Germany, there are several serial numbers: GS-711 (hardness 34~36HRC), GS738 ( Hardness 32~35HRC), GS808VAR (hardness 38~42HRC), GS318 (hardness 29~33HRC), GS312 (hardness 29~33HRC), GS312 contains sulfur and cannot be used as EDM pattern. It is more common to make mold bases in Europe. The code of GS312 is 40 Cr MN Mo S8, made by BOHLER Austria, serial numbers are: M261 (38~42HRC), M238 (36~42HRC), M202 (29~33HRC), M202 cannot be made of EDM pattern, it also contains sulfur, and there are Other brands cannot be listed.
　　 (three) X 40 CrMo V51 hot work steel
The United States, China, Hong Kong, Singapore, standard code: AISI H13, DIN: (Europe) 1.2344; Japan SKD61, the factory hardness of this kind of steel is: HB185 ~ HB230 must be heat treated.
The hardness used on plastic molds is generally 48~52HRC, and it can also be nitridated. Because heat treatment is required and processing is more difficult, the price of the mold is more expensive. If it needs heat treatment to a hardness above 40HRC, the mold generally uses machinery. Machining is more difficult, so the rough machining of the workpiece must be done before the heat treatment, which is: water holes, screw holes, and tapping must be done before heat treatment, otherwise it will be time-consuming and troublesome to anneal and redo. This kind of steel is also commonly used in plastic molds, so there are many brands. The brands commonly used in our factory are: ASSAB (ASSAB) and their serial number is 8407; THYSSEN and their serial number are GS344ESR or GS344EFS . (We generally use GS344ESR for ordering parts and GS344EFS for moving parts); Japan's Datong Steel DAIDO STEEL HI (mostly designated by Japanese customers), there are still many brands, because our factory is not commonly used, so we cannot Exhausted.
　　 (four) X45 Ni Cr Mo 4 cold work steel
AISI6F7 European number: DIN 1.2767, the factory hardness of this steel is HB260, which is required
Heat treatment, the general application hardness is 500 ~ 540HRC, European customers often use this steel, this steel is tough
The performance is good, and the lighting effect is also very good. Because this steel is not common in South China, there are not many brands. Our company uses THYSSEN GS767
　　 (five) X42 Cr 13 (stainless steel)
AISI: 420 STAVAX DIN: 1.2083 Factory hardness HB180~240, heat treatment is required, application hardness 48~52HRC, not suitable for nitriding heat treatment (cracking at sharp corners). This steel has good corrosion resistance and polishing effect, so generally transparent rubber parts and corrosive rubber materials, such as PVC and fireproof materials, V2, V1, and V0 plastics are very suitable for this kind of steel, and this steel is also very common. Used in plastic molds, so there are many brands. Our company commonly uses: ASSAB (ASSAB) S-136ESR
THYSSEN (THYSSEN) GS083-ESR, GS083 GS083VAR; if using THYSSEN, pay attention, if it is a transparent part, then the fixed and movable mold inserts must be GS083ESR (according to the data of the steel plant, ESR electroslag remelting is to improve the crystal of steel Uniform, better polishing effect), it is not a transparent plastic part. The movable mold part generally does not need high finish. Ordinary GS083 can be used. Because the price of steel is relatively cheaper, it will not affect the quality of the mold. This steel material is sometimes also used by customers. It is required to be used as a mold base. Because of the anti-rust relationship, it can ensure the smooth water transportation of the cooling pipe to achieve a stable production cycle. There are still many brands of this steel grade, which cannot be listed.
　　 (six) X 36 Cr Mo 17 (pre-hardened stainless steel)
DIN: 1.2316, AISI 420 STAVAX, factory hardness HB265~380, depending on the specifications of the steel plant, if it is a transparent plastic part, our company generally does not use this steel, because when it is polished to a high finish, it is easy to have pits due to insufficient hardness. At the same time, it is easy to have flower marks in beer plastics, so it needs to be polished frequently, so we still use 1.2083 ESR to harden and harden to 48~52HRC after heat treatment, which saves a lot.
(Although the hardness of this steel is not high, mechanical cutting is easier, and the mold completion cycle is shorter).
Most of our company uses this steel for medium-priced molds with anti-rust function, such as corrosive plastic materials, such as the PVC, V1, V2, and V0 mentioned above. This steel is also commonly used in plastic molds, and there are many brands. , Our company’s commonly used brands: ASSAB (ASSAB) S-136H, factory hardness is HB290~330, THYSSEN (THYSSEN) GS316 (HB265~310), GS316ESR (30~34HRC), GS083M (HB290~340) ), GS128H (38~42HRC), DAIDO PAK90 (HB300~330).
　　(7) X 38 Cr Mo 51 hot work steel
"AISI H11" European DIN 1.2343, the factory hardness of this steel is: HB 210~230, heat treatment is required, the general application hardness is: 50~540 HRC, according to the data of the steel plant, the toughness of this steel is slightly higher than 1.2344 (H13), in Europe It is more commonly used. Our company also uses this steel for fixed and movable mold inserts. Because this steel is not popular in Asia and the Americas, there are not many brands. Only 2 to 3 brands are in Hong Kong. Our company uses: GS343 EFS from THYSSEN. This steel can be nitrided.
　　 (eight) S 7 heavy-duty tool steel
The ex-factory hardness is: HB200~225, heat treatment is required, and the applied hardness is: 54~58 HRC. This steel is generally required by American customers to be used in fixed and movable mold inserts and row positions. It is not common in Europe and South China. The brands used by our company are: ASSAB (ASSAB) COMPAX-S7, and THYSSEN (THYSSEN) GS307.
　　 (9) X 155 Cr VMo 121 cold work steel
AISI D2 European number: DIN 1.2379, Japanese JIS SKD11 factory hardness: HB240~255, application hardness: 56~60HRC, can be nitrided, this steel is mostly used in the mold position (Japanese customers are more commonly used). Brands include: ASSAB (ASSAB) XW-41, Datong Steel Plant (DAIDO) DC-53 / DC11, Desheng Steel Plant (THYSSEN) GS-379.
　　 (10) 100 Mn Cr W4 & 90 Mn Cr V 8 oil steel
AISI 01, DIN 1.2510 & AISI 02, DIN 1.2842 Factory hardness: HB220~230, heat treatment, application hardness 580~600HRC, this steel is used on plastic molds, which are generally row gaskets and trash nails. Brands are: one ASSAB (ASSAB), DF2, THYSSEN GS-510 and GS-842, Long Kee (LKM) 2510.
　　(11) Be Cu
This material is generally used in places where it is difficult to cool plastic molds, because copper has a much faster heat dissipation effect than steel. The brand is: MOLDMAX 30/40, and the hardness is 26~32HRC and 36~42HRC. Desheng (B2) factory hardness For 35HRC.
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　　 (12) AMPCO 940 alloy copper
The factory hardness of this material is: HB 210. It is also used in molds where it is difficult to cool. The heat dissipation effect is also ideal, but it is softer than beryllium copper, its strength is not as good as that of beryllium copper, and the output is not that large. Can be considered.