Low-temperature Mechanical Properties of 00Cr17Ni12Mo2 (AISI 316) and 00Cr17Ni14Mo2 (AISI 316L) Steel
Low-temperature mechanical properties of 00Cr17Ni12Mo2 (AISI 316) and 00Cr17Ni14Mo2 (AISI 316L) stainless steels are important in many applications. These steels are commonly used due to their high corrosion resistance and high-temperature strength. However, it is also important to understand their low-temperature mechanical properties, as these can influence their performance in some applications such as cryogenic tanks and equipment.
AISI 316 and AISI 316L are austenitic stainless steels, consisting of a combination of iron, chromium, nickel and molybdenum. AISI 316 has a higher nickel content than AISI 316L, and thus has a higher level of corrosion resistance. AISI 316L, on the other hand, has a higher molybdenum content and thus has a higher level of wear resistance and improved mechanical strength.
At low temperatures, both AISI 316 and AISI 316L have greater ductility and higher tensile strength than at higher temperatures. This increase in strength is especially true for AISI 316, which also has an increased yield strength at low temperatures. The higher yield strength of AISI 316L can, however, be offset by its higher ductility at low temperatures, increasing its overall strength.
The impact strength of both steels is significantly impacted by low temperatures. Impact strength of AISI 316 decreases increasingly as the temperature drops further below room temperature, while the impact strength of AISI 316L is comparatively higher.
The hardenability of AISI 316 is better than that of AISI 316L and is capable of forming more complex, sharp geometries such as threads. AISI 316L is, however, more resistant to deformation at low temperatures and is thus often used to make cold formed parts such as screws and bolts.
AISI 316 and AISI 316L also show different characteristics when subjected to thermal treatments. AISI 316 is much more ductile and tougher which makes it more suitable for drawing and operations like bending and stamping. AISI 316L, on the other hand, has higher strength at lower temperatures which makes it more suitable for cold forming processes.
Both steels offer a combination of properties that make them suitable for a range of applications at lower temperatures. However, it is important for designers to understand the low-temperature characteristics of both these stainless steel grades to ensure that the most suitable grade is chosen for the application.
