317LMN (UNS S31726)合金是以鉬為基礎的奧氏體不銹鋼，具有很強的抗化學侵 蝕能力。另外，與常規的不銹鋼相比，317MN 合金具有更高的延展性、抗應力斷 裂、在高溫下較高的耐壓強度。它是低碳等級或L 等級， 這個等級具有在焊接期 間及熱處理過程中抗敏化作用性能。M 和N 分別指較高的鉬及鎳含量。鉬和鎳含 量使其具有較強的抗斑蝕和裂隙腐蝕能力，尤其是在高溫的含有酸、氯化物、硫 化合物溶液中。氮含量提高了其強度。這個不銹鋼合金在所有的標準等級的不銹 鋼中抗水腐蝕能力最高。
TAINLESS ACID RESISTANT STEEL 1.4439, AISI 317LMN, UNS S31726 WITH AUSTENITIC STRUCTURE RESISTANT TO INTERGRANULAR CORROSION ACCORDING TO EN 10088-1.
| Standards | Steel Grades |
|---|
| Chemical Composition % |
|---|
| C: | Mn: | Si: | P: | S: | Cr: | Ni: | Mo: | N: |
|---|
| EN | 1.4439 - X2CrNiMoN17-13-5 - X 2 CrNiMoN 17-13-5 |
| <0.03 | <2.0 | <1.0 | <0.045 | <0.015 | 16.5 - 18.5 | 12.5 - 14.5 | 4.0 - 5.0 | 0.12 - 0.22 |
| EN | 1.4434 - X2CrNiMoN18-12-4 - X 2 CrNiMoN 18-12-4 |
| <0.03 | <2.0 | <1.0 | <0.045 | <0.015 | 16.5 - 19.5 | 10.5 - 15.0 | 3.0 - 4.0 | 0.1 - 0.2 |
| ASTM | UNS S31726 - AISI 317LMN |
| <0.03 | <2.0 | <1.0 | <0.045 | <0.030 | 17.0 - 20.0 | 13.5 - 17.5 | 4.0 - 5.0 | 0.1 - 0.2 |
| AFNOR | Z3CND18-14-05Az - Z 3 CND 18-14-05 Az |
| <0.03 | <2.0 | <0.75 | <0.035 | <0.010 | 17.0 - 19.0 | 13.0 - 15.0 | 4.0 - 5.0 | 0.12 - 0.20 |
1.4439, X2CrNiMoN17-13-5, AISI 317LMN - specification and destination
Type 1.4439 is a derivative and better austenitic variant of the 316 and 317 steel grades, having higher Nickel, Molybdenum and Nitrogen content, which significantly increases the product's resistance to pitting and crevice corrosion in Cl environments.
Stal finds its application in the chemical, energy, cryogenic, petrochemical, pulp and paper industries as well as in food contact with chlorides and the effects of high temperatures.
It shows a better yield point up to 400 ℃ compared to 1.4438, 1.4436, 1.4435 and 1.4432.
It is used for the production of special pumps, installations, radiators, apparatus, heat exchangers or tanks for chemicals - sulfuric, formic, nitric, acetic or sodium hydroxide in the form of bars, forgings, sheets and pipes.
The process of heat treatment - supersaturation is carried out at 1020 - 1120 ℃
Mechanical and physical properties of 1.4439, X2CrNiMoN17-13-5:
Tensile strength, Rm: 580 - 800 MPa
Yield point, Rp0,2: >280 MPa
Elongation, A: >35%
Impact resistance, KV20℃: >100 J
Hardness: <250 HB
Heat conductivity, λ: 14 W * m-1 * K-1
Heat capacity, cp20℃: 500 J * kg-1 * K-1
Modulus of elasticity, E: 200 GPa
Specific resistance, Ω: 0.85 mkOhm * m
Mechanical properties at elevated temperatures
