In simplistic terms punches, dies and forming tools generally involve a fabrication process of "brute force" to pierce, cut, form, or create a piece of material. This type of process is sometimes referred to as "chipless" cutting. Today's tool/die buyers and tool/die machinists need to be more knowledgeable than the characteristics of the raw steel used to make the blank. They need to understand the synergy that are involved in the entire system: tooling design, making raw materials for tooling, processing & heat treatment, coating properties, material being machined, cycle time requirements, and allowable machine downtime.
Coating Benefits for Punches and Dies
Based on the needs of your project, ACS can offer a variety of PVD coatings that enhance the value and decrease the total cost of punches, dies and forming tools. Combining low friction coefficients with high film hardness gives rise to the desirable properties of:
decreased sliding friction
Increased wear resistance to abrasive abrasives
reduced punch & die retraction forces
increased surface hardness & toughness
enhanced pill tablet release from tablet punches
Reducing galling, adhesive wear, and material pick-up
Eliminating the material reaction caused by chemical inertness
These enhancements must be achieved while maintaining the crucial dimensions, tolerances, and punches that dies as well as making instruments require using them. This is the reason PVD is so useful in providing functional surfaces.
GROW LONGER OVER YOUR LIFE ESPAN OF DIES and PUNCHES. TOOLS
Punches, dies, and forming tools can experience significant improvements in their lifespans when they are coated with PVD thin film coatings. The Platit Arc deposition systems allow for full control of deposition temperatures ranging from 160oC to 490oC. These temperatures are suitable for many of the water, oil, or air hardening steels such as S1, S7, A2, D2 W1, D3, W2, O1 & M1 and M2, T1, M4420SS, other alloys and powdered metallics that are utilized in the production of die tooling and other tools for forming, and materials such as tungsten carbide.
PVD VS CVD COATING
PVD is preferable to CVD in coatings for punches, dies, and forming tools due to the lower temperatures that PVD uses during processing to safeguard the hardness that is treated with heat and austenitizing temperatures of the forming tool's substrate materials.
TIGHTER TOLERANCE
PVD can produce coating thicknesses ranging from 0.00004" to 0.00020", so parts can be machined to the desired size prior to coating. This allows for close tolerance punch or die applications to have the necessary clearances.
INCREASE WEAR RESISTANCE
The term "wear" is used to describe the effect of corrosion or abrasion on contact with other substances such as tools, grit and/or equipment. A die, punch or making tool's resistance to cracking, breaking or chipping could be described as "toughness". Every material used in fabrication of a punch has its own wear characteristics and toughness. These materials are available in the following options:
Low wear resistance and high toughness
ADVANCED wear resistance and toughness
High wear resistance and LOW toughness
The tooling material that is best suitable for the particular application will depend on the manufacturing process it follows. Wear resistance is also affected by the degree of hardness and coatings applied on the tool.