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Plastic Mold Steels

Porcerax II

General Properties:

Average pore size: 7 or 20 microns
Porosity: 25% air by volume
Linear Expansion: (@68 - 302F) 6.67 - 6.94 in./in F

Heat transfer co-efficient (at room temperature): 
16.93 - 19.35 BTU/ft. hr. F
Tensile strength:63990-71100 lbs./In2
Hardness: HMV 350 - 400 (35-40 HRC)
HSS Machinability: Good
Polishability: Good


Machining and Polishing
Porcerax II can be machined by conventional methods using cutoff saws, end mills, grinders, EDM methods, stoning, etc. It is important to remember that this material is honey-combed with thousands of microscopic holes which are affected by metal removal. Oil coolant is recommended.

Grinding closes the pores of all grades of this porous steel. Milling will close the pores of 7 micron and reduce the pore size of the 20-micron material down to about 7 microns
(when done correctly) by partially closing the pore opening at the surface. Stoning, using a back and forth/side to side method, will re-establish permeability by removing the metal that is crushed over the pores. Stoning and polishing, up to about a number 800 - 1000 stone/paper finish, is possible. During the stoning and polishing process, it is important to occasionally flush the pores at the surface to prevent packing the pores with debris.

Electric Discharge Machining is the best way to re-establish permeability. This method will burn away the metal fragments that are crushed over the pores by milling and/or grinding.

Note: When using wire EDM machining methods, Porcerax II is porous and generates
waste particles that can create "arcing" conditions between the wire and the work-piece.
This arcing can cut the wire. As a countermeasure, increase wire winding speed.

Note: When using an electrode for EDM, it is important to program a peak-to-valley burn rate that exceeds the pore size; i.e. < 7 micron depth for 7 micron pore size is desirable. 

The illustrations above show how particles created by the wire EDM process carry the
electrical current across to the work-piece, creating the potential for a discharge that can break the wire. Increasing the wire winding speed not only greatly reduces the potential for wire breakage but also increases machining times.

Important Warning:

It is imperative that anyone coming into contact with Porcerax II during the mold building or molding operations understand the characteristics and sensitivity of this material. Any questions should be directed to International Mold Steel at 859.342.6000.

NOTE: All technical and engineering data and suggested procedures, specifications and applications contained in this publication are for general information only. Sintokogio, Ltd., International Mold Steel and/or their distributors disclaim any and all express or implied warranties of merchantability, suitability for any particular purpose or use, or freedom from infringement of any patent, trademark or copyright. Porcerax II is a registered trademark of International Mold Steel, Inc. and Sintokogio, Ltd..





Recommended Reading

Unique Characteristics


General Properties

Post-Machining Treatments

Water Line Sealing

Design Guidelines

Cleaning, Maintenance, and Resin Removal

Porcerax II Insert Installation

Porcerax II Pin Installation

Discussion Forums



  International Mold Steel, Inc. 
1155 Victory Place
Hebron, KY 41048 USA 
Tel: 859.342.6000
Fax: 859.342.6006
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