ExEll™ P20MDownload ExEll™ P20M Spec sheet
ExELL™ P-20m is a modified AISI P-20, premium quality Cr-Ni-Mo alloy tool steel which is normally supplied in the prehardened condition. Benefits of using ExELL™ P-20m include:
- No heat treat costs
- No heat treat risks or time lost
- Lowest tooling costs
- Can be surface treated (nitrided, flame hardened, plated, etc.) for any added surface performance
ExELL™ P-20m is used for a wide range of applications:
- Injection molds for thermoplastics
- Large compression molds
- Plastic extrusion and film dies
- Blow molds
- Zinc die cast dies
- Holders for die casting dies
- Structural or engineered components with prehardened properties
ExELL™ P-20m is produced to consistently high quality standards with these general characteristics:
- Good machinability
- Good polishability
- Good photoetching properties
- Uniform structure and mechanical properties
- Deep hardenability
Coefficient of Thermal Expansion, in/in/F
70-400 F 0.0000070
70-600 F 0.00000725
70-800 F 0.0000075
Thermal Conductivity, BTU in/ft2 hr F
70 F 202
650 F 205
1300 F 215
Modulus of Elasticity, psi
Specific Heat, Btu/lb F
In order to minimize any movement during service or tool making, stress relieving is normally performed between the rough and finish machine operations of tool making for prehardened material. Stress relieving is also regularly used after any welding. After rough machining, heat the part to 950F – 1000F (for prehardened material), equalize and hold 1 – 2 hours, cool in furnace to 600F and then air cool. Note: Insure that prior tempering temperature is not attained or exceeded during stress relieving or hardness level of prehardened material will be lowered.
With a protective atmosphere or vacuum furnace, heat slowly to 1300F. Equalize and hold one hour per inch of thickness. Furnace cool 20F/hr to 1000F and equalize. Air cool to room temperature. Hardness – 250 HB max.
HARDENING AND QUENCHING
Note: Heat treatment of machined parts involves a high risk of cracking. Minimize effects of thin and thick sections, sharp changes of section, machine marks, etc.
Preheating: Heat to 1000 – 1200F and equalize. Continue heating to hardening temperature.
Hardening: Protect against oxidation and decarburization. Austenitizing (hardening) temperature is normally 1560F. After heating to hardening temperature, equalize and hold 30 minutes at temperature.
Oil or polymer quench.
Martempering bath 850 – 1050F,
4 minutes maximum, then air cool.
Temper as soon as quenching temperature reaches 120 – 150F.
Temper immediately after quenching to about 150F. Temper two times with cooling to room temperature between tempers.
ExELL™ P-20m should be heated to the desired tempering temperature and held a minimum of two hours. Select the tempering temperature based on required hardness and prior quenching medium. Air cool to room temperature. Check hardness and
adjust temperature for second temper. Repeat for additional temper.
Typical tempering temperature responses are: (Use for approximate guideline only)
Hardness (Oil Quench)
|Tensile Strength (psi)
|Yield Strength (psi)
Our steel making expertise and capability is further enhanced from a long forging history with optimum forging and heat treating practices to develop very special material characteristics of product uniformity, cleanliness, machinability, polishability, strength, toughness, hardenability and other steel properties. All this from production facilities certified to ISO 9001.
Ellwood Specialty Steel is committed to providing products and services which will consistently meet or exceed all quality and performance expectations. We will provide customer and technical service that will ensure complete satisfaction.
Being a very flexible integrated producer, Ellwood Specialty Steel will establish product programs to fully support industry or customer requirements. Our extensive stock programs are supported by very short mill lead times of custom forged products. Customized stock programs are and can be available for specific customer needs.
This information is intended to provide general data on our products and their uses and is based on our knowledge at the time of publication. No information should be construed as a guarantee of specific properties of the products described or suitability for a particular application. Ellwood Specialty Steel reserves the right to make changes in practices which may render some information outdated or obsolete. Ellwood Specialty Steel should be consulted for current information and/or capabilities.