While stainless steel is required in many different types of applications, it is definitely not the easiest alloy to work with. In the great majority of projects any machining company will do, the type of stainless will fall into the austenitic types, which means they are prone to work hardening and have very poor chip breaking properties.
Successful stainless steel machining requires experience and expertise in working with this metal. Simple mistakes or poor quality of equipment or operator skills can result in very real challenges in getting an order completed to the tolerances and quality standards required.
Equipment Challenges
While operator experience is important in machining stainless steel, the quality of the equipment used is an extremely critical factor. New technology in CNC machining equipment provides the power and the technology to more effectively reduce issues that are common when working with this alloy.
Machining companies using old, outdated and incorrectly set equipment will have increased waste, problems with production and they may also have significant challenges in working to required tolerances and project specifications.
Drill speeds, both too fast or too slow, can be problematic. Vibrations in the equipment that may cause chatter will cause variations in the cuts, holes and lathe operations that will translate into irregularities and imperfections.
The specific types of tools also have to be carefully selected based on the type of stainless steel alloy and the actual process being used. In most cases, either high speed steel tools, usually made of tungsten or molybdenum, will be required. Cemented carbide tools can also be used, particularly where higher speeds on the tool will be required for the job.
Cooling the Metal
An essential part of stainless steel machining will be in choosing the best type of cutting fluid for the specific alloy and the operation. The cutting fluid will be used to both lubricate the metal to provide reduced wear on the specific tool, but also to cool the metal. Overheating of the surface of the stainless steel part or component during the Stainless Steel Machining Process can alter the final product.
These alterations can include changing the color at the site of the machining, known as heat tinting. This is not just cosmetic; it will also reduce the ability of the stainless to resist corrosion. It is also possible that too much heat will change the shape of the component slightly, often resulting in the component ending up as unusable scrap.