Steel for plastic molds
| Steel type | Equivalent JIS steel | Hardening and annealing hardness | Features | Application example |
| KPM1 | S55C | 27 to 32HS | Steel for general-purpose plastic molds | Large-size formed parts |
| KPMAX | 27 to 32HS | Highly machinable steel for general-purpose plastic molds | Large-size formed parts for cars and household appliances | |
| KPM30 | 27 to 33HRC | Hard and highly machinable steel for general-purpose plastic molds | Large-size formed parts | |
| KAP65 | 38 to 42HRC | High-quality free machining steel for plastic molds | High-quality formed parts | |
| KAP88 | 38 to 42HRC | High-quality mirror surface steel for plastic molds | High-quality formed parts | |
| 420M | SUS420J2 | 30 to 36HRC | Free machining corrosion-resistant steel for plastic molds | Molds for corrosive environments with salt water |
| KAP90F | SKD61 (Free machining) |
38 to 42HRC | Free machining plastic hardened steel | Ejector turbines and mold parts |
| SM3 | SUS440C (Hardening hardness) |
56 to 60HRC | Corrosion-proof and wear-proof steel for plastic molds | High-quality formed engineering plastic parts |
Recommended!
Recommended KPMAX
These are general-purpose steel for plastic molds that feature good machinability and uniform hardness from surface through to the center. Superior welding reparability and drawing machinability make this steel an attractive alternative for large-size plastic molds instead of S55C.
Recommended KPM30
These are the HRC30-type steel for plastic molds with the completely improved characteristics of the SCM440 steel for plastic molds. Their superior machinability contributes to the reduction of customersﾕ mold manufacturing time.
Characteristic chart of steel for plastic molds
