316L and 316LVM are each types of stainless steel alloy. Stainless steel is a type of metal alloy that contains at least 10.5 percent chromium and greater than 50 percent iron. Though it is called stainless steel it isn't impervious to stain, however it is highly stain resistant. Stainless steel is used in a variety of applications, including kitchen utensils and body piercing jewelry.
Types of Stainless Steel
Stainless steel comes in three basic classifications: austenitic, martensitic and ferritic. Austenitic stainless steel is a chromium-nickel-iron alloy that contains 16 to 26 percent chromium, 6 to 22 percent nickel and low carbon. Martensitic steel is a chromium-iron alloy that contains 10.5 to 17 percent chromium and a carbon content that is strictly controlled. Ferritic steel is a chromium-iron alloy that contains 17 to 27 percent chromium and low carbon. Martensitic and ferritic alloys have magnetic properties, while austenitic alloys do not. 316L and 316LVM are austenitic alloys.
Properties of Austenitic Alloys
Austenitic alloys have a higher resistance to corrosion than martensitic and ferritic alloys, due to the introduction of nickel into the alloy. The most commonly used austenitic alloy is type 304, which contains 18 percent chromium and 8 percent nickel. Austenitic alloys are created through a process of heating, cooling, then heating again. It is resistant to scaling and retains its strength at high temperatures. Due to these properties it is most commonly used in cooking utensils.
Grade 316 and 316L
Grade 316 alloy is the second most commonly used austenitic alloy, next to 304. 316 contains molybdenum, which makes it more resistant to corrosion than 304. Grade 316L is the low carbon variety of 316. Due to the low carbon content, 316L steel is immune to sensitization, a type of corrosion that occurs when stainless steel reaches high temperatures. Because of this property, 316L is commonly used in heavy gauge welded components.
316LVM is a variety of grade 316 stainless steel that is produced exclusively by Fort Wayne Metals Research Product Corp. 316LVM goes through a process of electric arc melting, followed by vacuum arc remelting that results in a highly uniform chemistry that contains a minimal amount of impurities. Due to its lack of contaminants and high resistance to corrosion, 316LVM is commonly used in temporary and permanent medical implants (sutures, surgical staples and bone pins) and body piercing jewelry.