Cold Heading Tolerances and Technical Data

Geometries

Geometries Not Suited for Cold FormingAutoCAD Drawing showing various shaps sutable for cold forming

 

There are geometric limitations to parts that can be cold formed. Above are some sketches of parts showing features that can and cannot be cold formed.

 

The drawing to the right has some features that can be put on by typical secondary operations.  Typical cold formed tolerances are shown on the diagrams. Tighter tolerances can be held if needed.


 

 

Material for Cold Forming

This a list (admittedly incomplete) of metals suitable for cold forming, and some that are not. A general guideline for cold formability is that the metal’s elongation must be at least 20%.

  View Properties Table

Suitable Alloy Cold Formability Characteristic
Copper  Excellent
Gold, Silver and most of their Alloys Excellent
Brass- Cartridge Brass  Good
Platinum, palladium, tantalum, and their alloys Most are cold formable.
Titanium and its alloys Pure Ti and alloys with high ductility, yes, but alloys like 6-4 are only hot headable.
Nickel and its alloys Pure Ni yes, alloys with room temperature elongation of 20% or more, yes.
Iron and steels Pure iron, yes. Steels, depends on the steel. Many are cold formable.
Non-Suitable Alloy Cold Formability Characteristic 
Brass-free machining grades (like C360) Poor- chip-breaking additives promote cracking. Use instead 260 brass.
Cast iron Too brittle
Silicon Too brittle
Tungsten Too brittle
Cobalt and cobalt alloys Generally too brittle
Rhenium Too brittle
Rhodium Mostly too brittle


Useful Links

www.copper.org                  Copper Development Association 
www.onlineconversion.org   Conversions from anything to anything else
www.engineersedge.com     Engineering Reference Directory 

For More Information

Contact Us to discuss your application with one of our engineers

 

Material Savings

Tantalum part. Cold forming is preferred over machining for this expensive material because there is so little scrap generated in cold forming.

 

Difficult to Machine Materials

Pure gold implantable marker. Cold forming can hold tighter tolerances than machining for this difficult-to-machine material.
 

Quality Control

We can create a control plan and inspection frequency that suits your needs. We can even do 100% inspection if that’s what the application requires.

 

Typical Applications

DNI produces parts for electromechanical switches, potentiometric sensors, invasive and implantable medical devices. We are an engineering-based company, and would be happy to talk with you about your application. Contact us for more info.