Our globally renowned portfolio of grades for metalforming and stamping is based on over 80 years of research and development of tungsten carbide-based materials.
We have a large selection of conventional and low-corrosion rectangular blanks in stock. Each is sinter-HIP processed and stress-relieved for optimum performance in EDM machining. Blocks are available in standard sizes, which are individually packaged for easy delivery and handling.
EDM Blocks Portfolio:
All grades are proven in their application.
Products stocked globally for quick delivery
Standard and corrosion-resistant grades
200 standard sizes with custom sizes available upon request
Application, metallurgical, and process optimization services
Withstand Extensive EDM
Our latest grades were developed with a proprietary binder system and maintain the hardness and mechanical properties of our conventional grades. They resist the corrosion, pitting, and cracking commonly experienced during electrical discharge machining, especially in thick punches and large die segments.
Cemented Tungsten Carbide Grades
We offer a wide variety of carbide grades, including submicron, fine, medium, and coarse-grained tungsten carbides with a mixture of binders and additives to create the right balance of hardness, toughness, abrasion, and corrosion resistance for the application.
Hardness: Hardness is determined by the percentage of binder and the grain size of the tungsten carbide particles. Generally, the more binder, the lower the hardness, and the larger the grains, the lower the hardness.
Wear Resistance: Generally, grades with more binder or coarser grains (lower hardness) will have less wear or abrasion resistance. However, there will be an increase in strength. It is always necessary to balance high hardness/high wear resistance with lower hardness/high strength. To test the abrasion or wear resistance of our carbide grades, we typically conduct a dry sand (G65) or slurry tests (B611).
Strength: The amount of binder and the variation in grain size will also affect the impact strength (a shock load) and the fracture toughness (a measure of crack initiation and crack propagation). More binder and/or coarser grains will generally increase the impact strength and the fracture toughness. With submicron grained grades, impact strength and the fracture toughness decrease when compared to coarser grained grades of equal cobalt content; however hardness increases.
EDM Blocks Grade Descriptions
Unlike other carbide manufacturers, we produce our powders from the raw materials. This guarantees the highest quality tungsten carbide throughout the process and maximizes performance for the end user.
Corrosion Resistant Binder Grades Optimized for the Wire EDM Process
Composition: 10% corrosion-resistant binder with submicron grain structure. Very good wear resistance with high edge sharpness but less shock resistance than higher binder grades. Excellent for EDM operations and good in non-ferrous applications.
Application: An upgrade to standard 10% submicron grades, KR855 presents ideal wear resistance in high-speed stamping, medium, thin sheets — coining brass (~.010" / 0.25mm thick), can die ironing rings, non-gummy steels, compacting dies, stamping dies for razor blades, lead frames (thin copper ~.030"/0.76mm), annealed copper, and draw dies (300 series stainless steel).
Composition: 12% corrosion-resistant binder with medium/fine-grain structure. Very high strength for medium impact with low wear properties.
Application: Light blanking dies - Silicon Steel up to ~.020" / 0.5mm, Medium Blanking - Mild Steel to ~.030" / 0.8mm Lamination dies - silicon steel, Scroll dies, burnishing rolls, backward and forward extrusion dies (light impact).
Composition: 15% corrosion-resistant mixed binder with submicron grain structure for lead frame and connector stamping. Very high strength and excellent wear resistance for medium-impact applications.
Application: Stamping dies for razor blades, electronic stamping, lead frame dies, laminations, spring steel stampings, and coining dies (hard metal). Not recommended for stamping thick stainless steel. Use in place of CD650 for difficult to EDM parts, or if corrosive die lubricants are used.
Cobalt Binder Grades Optimized for the Wire EDM Process
Composition: Conventional 15% cobalt binder with submicron grain structure for lead frame and connector stamping. Very high strength and excellent wear resistance for medium-impact applications. Our most popluar grade for general purpose stamping.
Application: Stamping dies for razor blades, electronic stamping, lead frame dies, laminations, spring steel stampings, coining dies (hard metal). Not recommended for stamping thick stainless steel.
Composition: 15.5% cobalt binder with ultrafine submicron grain structure for lead frame and connector stamping. Very high strength and excellent wear resistance for low-impact applications.
Application: Extremely thin punches or tools with very fine features will benefit from the ultrafine submicron grain structure, which helps to prevent premature corner washout and maintain edge strength. Also, may be used as an upgrade to CD650, due to increased hardness.
Composition: This 12% Cobalt grade is well suited for high impact stamping and bending applications due to its coarse grain structure and high fracture toughness.
Application: Impacting punches, Coining dies, Forming dies, Can die punches, Swaging dies, Cold forming, Back extrusion punches & dies, high-impact extrusion dies, Nail grip dies, Very severe draw dies for .075" thick cold rolled steel, Piercing punches-305 stainless, Works well on gummy steel.
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