Plastic Air Cooler Part Mould

How to choose the mould steel for the plastic air cooler part mould?

Usually, the plastic mould steel choices include Swedish 8407 and S136; American 420 and H13; European 2316, 2344 and 2083 and Japanese SKD61. For strongly corrosive plastics, S136, 2316 and 420 steels are usually chosen. In addition to S136, 2316 and 420 steels, low corrosion plastics can also choose SKD61, NAK80, PAK90 and 718M steels. Mould steel also has a great influence on product appearance. S136, 2316, 718S, NAK80, PAK90 and 420 steel materials are suitable for clear and high polishing surface products, while highly transparent products should primarily select the S136, and secondarily choose the 420 steel materials.

Common used plastic mould steels

1. NAK80

Series: Pre-hardened steel

Hardness: 37-42HRC

Manufacturer: DAIDO; Fushun

Performance & Purpose: Pre-hardened and corrosion-resistant stainless steel for plastic injection mold, mirror-polished mold; the steel is extremely brittle and easy to crack due to concentration of processing stress when complicated molds are involved. When welding, the hardness of the welded part will decrease, but after aging treatment and air cooling under 500°C temperature conditions for 5 hours, the welded part and the heat-affected area will be of the same hardness as the substrate.

2. 1.2344

Series: Hardened up steel

Hardness: 50 ~52HRC

Manufacturer: BUDERUS

Performance & Purpose: Pressure-resistant hot-working mold steel; excellent machinability and polishing performance, high toughness, and plasticity; great wear resistance at high and low temperatures, resistance to thermo-mechanical fatigue and heat. Mold cores, inserts, ejector pins, and sleeves.

3. 1.2311

Series: Pre-hardened steel

Hardness: 30-34HRC when leaving the factory; preheat it for 2-4 hours under 500-600℃ temperature conditions before quenching, then keep it in the 850-880℃ temperature condition for a certain period of time (at least 2 hours); after that, oil cool the steel to 50-100℃ before air cooling; after quenching, the hardness can reach up to 50-52HRC; to prevent cracks, immediately temper it under the 200℃ temperature conditions, after which the hardness can stay over 48HRC, and reach up to 650-700HV (57-60HRC) after nitridation

Manufacturer: BUDERUS

Performance & Purpose: After thermal treatment, the 2311 pre-hardened plastic mold steel possesses great processing and polishing performance, and is more suitable for EDM. Generally, it can be used for the production of large plastic molds and plastic mold bases.

4. 1.2738

Series: Pre-hardened steel

Hardness: 29-33HRC when leaving the factory, and can be quenched to 52HRC; carburized hardness is 55-60HRC, nitrided hardness is 650HV (Depth 0.29/.36/.5)

Manufacturer: BUDERUS

Performance & Purpose: Mainly used in large-size plastic molds and mold bases, such as molds of vehicle bumpers and TV shells. It is suitable for molds that require high gloss and high uniformity, such as the production of hard (PS) and ultra-hard (ABS) rubbers. It is suitable for plastic molds and mold bases of such parts as TV front shell, telephone, water dispenser, and vacuum cleaner.

5. 718

Series: Hardened up steel

Hardness: HB: 290-310 when leaving the factory, and can be quenched to 48-50HRC, nitrided hardness is 650HV-700HV (Depth 0.29/.36/.5)

Manufacturer: ASSAB; Fushun

6. 718H

Series: Pre-harden steel

Hardness: 35-39HRC, and can be quenched to 48-50HRC, nitrided hardness is 650HV-700HV (Depth 0.29/.36/.5)

Manufacturer: ASSAB; Fushun

Performance & Purpose: Suitable for cores, inserts, and slides of home appliances and computer molds.

7. 738

Series: Hardened up steel

Hardness: 37-42HRC

Manufacturer: Saarstahl

Performance & Purpose: The core steel of general molds, the mold base of high-level molds.

8. P20

Series: Pre-hardened steel

Hardness: 285-330HB (30-36HRC), nitrided hardness reaches up to 650-700HV (57-60HRC)

9. SKD61

Series: Hardened up steel

Hardness: 56-58HRC nitride

Manufacturer: Hitachi; Fushun

Performance & Purpose: The material features low hardness, great tenacity, and poor optical rotation performances, poor wear- / corrosion-resistant, prone to rust, with a low price, mainly used for the production of mold bases, unimportant parts, and trial molds; only carburizing can be adopted to improve the surface hardness of the material to HRC52-56. Other thermal treatments, such as quenching and nitriding are not applicable.

10. H13

Series: Hardened up steel

Hardness: HRC43-45

Performance & Purpose: The optimal heat treatment condition for the H13 material is to quench it to the hardness of HRC43-45.

Also, there are other choices for mould steel, if you have any problem, you can contact SWY MOULD to have a talk.