Dawson Shanahan has developed an innovative production process that the company claims could revolutionise the way stainless steel parts are made. The new process enables high-precision stainless steel parts to be produced quickly, efficiently and with minimal scrap, making the process suitable for applications in the automotive, medical and aerospace sectors.
Cold forming is a simple extrusion process based on forcing a metal at room temperature beyond its elastic limit, yet without affecting its tensile strength. Unlike hot forging or casting, the strength of the metal piece in question can be increased by the process; similarly, by comparison with milling or turning, cold forming produces parts with greater mechanical integrity and highly polished internal surfaces, with up to 70 per cent less waste metal.
Until now, cold forming has generally been used with ductile materials such as aluminium, copper and brass. Cold forming tougher and more brittle alloys such as stainless steel has eluded most precision engineers, or has only been achieved using extremely expensive and often hazardous and/or environmentally unfriendly techniques.
Dawson Shanahan, however, has now developed a method of cold forming, using specialised material lubrication and protection coatings, allied to enhancements in the forming process. These enable high quality stainless steel parts to produced, while retaining all of the traditional benefits associated with conventional cold forming.
The company has already carried out extensive prototype tests, with components being tested for material and part integrity by an independent laboratory. Mark Jennings, Technical Director at Dawson Shanahan, states: "This development allows larger stainless steel components to be cold formed on a commercial scale. We are now able to produce both small- and high-volume parts, with complex internal geometries and at levels of quality that match or surpass anything that can be achieved using standard machining procedures."
Stainless steel parts produced through cold forming can be used in applications where conventionally manufactured items would be unsuitable in terms of cost or quality. For example, cold formed stainless steel engine components can offer performance improvements over machined components. Similarly, high-precision, cold formed stainless steel parts can also be manufactured by Dawson Shanahan to meet the demands of the medical, aerospace and automotive sectors.