Stainless steel is a popular metal in construction, aerospace and the automotive industries. Fabricators and other metal workers use it for its durability and corrosion-resistant properties. The availability of many different grades makes it versatile in its applications. However, machinists know the metal has a major problem – a low machinability rating. When it comes to stainless steel machining, those who work with metal must be completely aware of what grades are appropriate and which to avoid.
Machining
When it comes to cutting stainless steel bars, sheets or plate, machining is a serious process. Machining can take the metal and shape it into precise forms suitable for a variety of industries, including aerospace and automotive manufacturing concerns. While manual machining can work with stainless steel, it is best for only simple shapes. If the work requires more complexity, machinists rely on CADCAM software programming CNC machines.
The Difficulties of Stainless Steel Machining
Stainless steel has a low machinability rating and is subject to “work hardening.” However, certain grades have a higher rating than others do. While the 400 series is easiest to machine, it is susceptible to stringy chipping reducing productivity. As a result, more machinists favor using free-machining stainless steel. This type of stainless steel features an additive or either sulfur or selenium. By adding either element to 303 or many of the 400 grades, it is possible to improve the ease of machinability. Optional additives include:
Lead – 303SE
Copper – 430F
Alum – 416
Phosphorous – 420F
All work with stainless steel to improve machinability.
Successful Stainless Steel Machining
Machining stainless steel is fraught with potential problems. Improper handling of the metal can result in seriously flawed workpieces. Working with a reputable machine shop – one that recognizes the different grades of stainless steel will make the process easier. These professionals understand successful stainless steel machining requires utilizing free machining steel grades – ones in which contain selenium or sulfur additives.
