Cold forming – an alternative process that forges metals at near room temperatures

As eco-friendly production methods grow increasingly popular, the energy efficient Cold Forming technique does well in beating the heat

Cold forming or cold working is any metalworking process in which metal is shaped below its recrystallization temperature, usually at the ambient temperature.

Both the production and manipulation of metals has long been associated with high temperatures.

Since man moved beyond the use of naturally occurring materials like wood and stone, and what was likely an accidental discovery cooking in a fire or a potter’s kiln, a major part of metal production has been carried out in processes that employ temperatures in the range of 300 to 1600°C.

Therefore, you might be surprised to learn about about this alternative process that forges metals at near room temperatures.

Cold Forming - A15 coffee table by Atlas Manufacturing — A15 coffee table by Atlas Manufacturing use blackened cold-rolled steel with bronze accents for the legs and structure – Image via Atlas Manufacturing

What materials can be cold formed?

Cold forming is a simple process that produces metal components at low temperatures without removing any material.

Materials that can be cold formed include, but are not limited to: carbon steels, brass, lead, stainless steel, copper, alloy steels, aluminium, bronze, nickel alloys and precious metals.

What can I use cold forming for?

As with other metal processing techniques, the applications of are wide-ranging.

It can be used to create large flat sheets, complex folded shapes, metal tubes, screw heads and threads, riveted joints, and much more.

Cold Forming - A11 Table side view — A11 Table by Atlas Industries made of a walnut top with blackened cold-formed steel with bronze accents – Images by John Halpern via Atlas Industries

In addition to small parts like screws, nuts, and bolts, it’s also possible to manipulate metals on a larger scale like body components, structural components, and exposed panels used in cars.

Curious to know more about products created using metal? Don’t miss The sustainable-inflatable design language of Zieta for stylish metal furniture.

Cold Forming - AD7 Desk by Atlas Manufacturing detail — AD7 Desk by Atlas Manufacturing uses solid white oak & cold-formed steel legs – Image by Rich Gilligan via Atlas Manufacturing

A step-by-step description of the process works

That’s a little tricky.

In a nutshell, cold forming techniques are usually classified into four major groups:

squeezing
bending
drawing
shearing

all of which share different stages of production to achieve the desired result.

Generally, the process always shares the same method of placing a bar stock of the material into a die and then squeezing it with a second closed die.

The deformation starts at room temperature and changes the shape and size of the initial part until it has assumed the shape of the die.

Steps — The cold forming process always shares the same method of placing a bar stock of the material into a die and then squeezing it with a second closed die

What are the pros & cons?

It goes without saying this process is much safer and less hazardous because of the low temperatures – conditions that also benefit the final material.

Unlike hot working, cold forming can improve quality and performance because the process causes the crystal grains and inclusions to distort following the flow of the metal.

This can actually harden the final product and create anisotropic material properties, making the metal stiffer, and stronger.

Other benefits include the fact that it’s less energy-intensive than traditionally high-temperature production.

Is it sustainable?

As it is less energy-intensive, it is more sustainable than other methods.

Short production cycles also make it less time consuming and less wasteful due to net shape methods.

On the whole, producing on a larger scale can therefore lead to significant savings, especially with expensive materials like copper, nickel, gold, tantalum, and palladium.

https://www.youtube.com/watch?v=wsMuoqgUCjA

Can I do it at home?

Unfortunately, cold forming requires a need for heavy equipment and hard tools, making it suitable only for large volume manufacturing.

Another, more significant disadvantage, is that cold-forged metals are less ductile, which makes them inappropriate for certain types.

Fire Tools by Atlas manufacturing — Modern tools for the fireplace by Atlas Manufacturing in blackened cold-formed steel – Image via Atlas Manufacturing

Also, because of the grain structure that gives the material its strength, undesirable residual stress may occur in the final piece.

It is important to mention that cold forging extrusion, for example, requires a heat treatment to eliminate possible flaws including cracks, creeks hardening, or rafters.