AISI 4140 – Steels For Molds Tools And Die
A prehardened mold steel (311-345 HB / 33-37 HRC) with improved machinability
41X40 is a chromium-manganese-molybdenum grade designed for plastic mold industry. This grade is normally delivered in a prehardened condition at a hardness level of 33/37HRC. The grade has a fully homogeneous martensite-bainite microstructure. 41X40 grade has specific sulfur addition (0.060% typical) in order to increase strongly its machinability. Compared to AISI P20 grade, 30% increase in milling speed and 300% increase in drilling speed can be expected. At constant cutting speed, tool life is multiplied a least by 5 when replacing P20 by 41X40 grade.
41X40 is not suitable for polishing requirements.
This grade is typically used for:
1.Plastic injection molds for thermoplastics
2.Extrusion dies for thermoplastics
Typical values (weight%)
Typical values for plates air quenched and tempered (thickness 45 mm – 1.8”).
Typical delivery sizes
|20 – 120 mm
(.79″ – 4.7″)
|1500 – 2500 mm
(59 – 98.4″)
|120 – 600 mm
(4.7″ – 23.6″)
|1500 – 2100 mm
(49″ – 82.7″)