Considerations and Advancements in Powder Metal Tool Design
Getting the perfect powdered metal (PM) part starts with, and is often contingent on the design and manufacture of quality tooling. Sterling Sintered designs all of our tools in-house, and has done so since 1955. That experience has taught us well what works and what doesn’t when it comes to tooling design. We do subcontract some tool manufacturing to our approved tooling houses when demand exceeds our internal capacity.
Powder metal tooling comes with a lot of the same design considerations that other compaction press tooling requires–factors like wall thickness, material strength, durability, and lifespan. However, powdered metal manufacturing poses its own challenges to tooling design. The compaction tools have to withstand forces anywhere from 60,000 to 100,000 PSI. These forces are not just axial on the punches but are also experienced in a hoop stress direction. To address these design considerations, Sterling Sintered has seventy years worth of tricks up our sleeves that we won’t divulge here, but let us help you with your part and you will benefit nonetheless.
Metal powders don’t flow hydraulically the way liquids do because of the friction between the powder particles and the die surfaces. Because of this, compaction tooling has to take into account that friction in order to ensure adequate powder distribution within the die cavity. PM tools often undergo a great deal more wear from the metal powder in terms of abrasion and impact than other tooling might experience in its daily operations.
Compaction tools, as mentioned above, come with a lot of the same requirements as tools for other presses–they have to mirror the part design, maintain constant pressure, resist breakage and more. Since powder metal tooling deals with powder, rather than liquid, they tend to require more protection against wear as well as a surface finish with reduced friction in order to ensure the powder fills the entire cavity.
New heat treatments and better metal coatings such as electro platings and PVD can protect the tooling and enhance its durability, while new stronger alloys offer the long lasting durability that is necessary to the process. Advances in manufacturing technology have helped as well, such as CNC wire and electrode EDM for providing highly accurate machining for better quality and precision. Better materials have been tailor-made for the powdered metal compaction as well, meeting the high strength requirements.
At Sterling Sintered, we are here to help you with any PM part design, and will guide you through all considerations necessary for the design and manufacture of tooling for your parts. For more information about how we can help you, or if you’re looking to partner with us, check out our website today.
