，关于 00Cr17Ni12Mo2N (AISI 316N) and 00Cr17Ni13Mo2N (AISI 316LN) steel high temperature mechanical properties
High Temperature Mechanical Properties of 00Cr17Ni12Mo2N (AISI 316N) and 00Cr17Ni13Mo2N (AISI 316LN) Steel
00Cr17Ni12Mo2N (AISI 316N) and 00Cr17Ni13Mo2N (AISI 316LN) steels are austenitic stainless steels that feature a combination of high strength, good ductility and excellent resistance to high temperature corrosion. They are widely used in the manufacture of chemical plants and equipment, food processing, power generation and general applications requiring protection against aggressive environments.
The high temperature behavior of these steels is primarily caused by their austenite-based microstructure which provides good mechanical strength, while still allowing them to maintain a high degree of resistance to long term exposure to high temperatures. Both steels have similar mechanical properties when in the solution-annealed condition with tensile strengths ranging from 540 to 620MPa, yield strength from 230 to 300MPa and elongation from 40 to 50%. At high temperatures, however, 00Cr17Ni12Mo2N (AISI 316N) steel has higher yield strength and lower ductility than 00Cr17Ni13Mo2N (AISI 316LN) steel.
When exposed to temperatures above 800°C, the material properties of these steels drastically change. As the temperature increases, there is an initial decrease in the yield strength followed by a significant decrease in the ductility of the material. At temperatures above 1100°C, both 00Cr17Ni12Mo2N (AISI 316N) and 00Cr17Ni13Mo2N (AISI 316LN) steels show low yield strength, high strain hardening rate and low plastic deformation capability. This behaviour is a result of the higher magnitude of onset of austenite grain boundary sliding, displacement of martensite relative to the grain boundaries and acceleration of grain boundary migrations in the steels.
The high temperature creep properties of these steels are determined by the creep strain rate which is defined as the amount of strain experienced by a material over a given time period for a given stress level. 00Cr17Ni12Mo2N (AISI 316N) and 00Cr17Ni13Mo2N (AISI 316LN) steels show a higher creep strain rate than other austenitic steels when tested at temperatures higher than 900°C. Both steels have similar creep strain rates when exposed to temperatures below 900°C, but 00Cr17Ni13Mo2N (AISI 316LN) steel has a lower creep strain rate than 00Cr17Ni12Mo2N (AISI 316N) steel at temperatures above 900°C.
The oxidation resistance of these steels is also affected by the high temperatures they are exposed to. 00Cr17Ni12Mo2N (AISI 316N) steel exhibits better oxidation resistance than 00Cr17Ni13Mo2N (AISI 316LN) steel when exposed to temperatures between 800-1150°C. At higher temperatures, however, the oxidation resistance of these steels is reduced due to the formation of iron oxides on the steel surface. It is also important to note that the oxidation rate increases with increasing temperature for both steels.
In conclusion, 00Cr17Ni12Mo2N (AISI 316N) and 00Cr17Ni13Mo2N (AISI 316LN) steels have good mechanical properties when exposed to temperatures up to 800C and show excellent corrosion resistance in aggressive environments. At temperatures above 800C, there is an initial decrease in the yield strength of the material followed by a drastic reduction in the ductility of the material. Both steels also show high creep strain rates at temperatures above 900C, with 00Cr17Ni12Mo2N (AISI 316N) steel having a higher creep strain rate than 00Cr17Ni13Mo2N (AISI 316LN) steel. Lastly, 00Cr17Ni12Mo2N (AISI 316N) steel exhibits better oxidation resistance than 00Cr17Ni13Mo2N (AISI 316LN) steel at temperatures between 800-1150°C.
