Qhov sib txawv ntawm 304 thiab 321 stainless hlau hauv kev siv tsheb
Qhov sib txawv ntawm 304 thiab 321 stainless hlau hauv kev siv tsheb
Hauv kev siv tsheb, 304 stainless hlau muaj kev tiv thaiv zoo ntawm qhov kub nruab nrab (xws li, cov kav dej tso pa, mufflers), thaum 321 stainless hlau, tom qab titanium stabilization, yog qhov tsim nyog rau siab - kub Cheebtsam (xws li, turbo manifolds, kev sib tw tsheb tso pa tawm manifolds) vim tias nws tiv thaiv kev ua kom muaj zog thiab muaj roj (carriage) tiv thaiv kev tawg thiab xeb uas tuaj yeem yooj yim ua rau tsis ua haujlwm ntawm 304 stainless hlau nyob rau hauv qhov kub siab heev -kub cycling. Yog li, 304 stainless hlau raug pom zoo rau kev siv txhua hnub, thaum 321 stainless hlau raug pom zoo rau kev ua haujlwm siab -kev ua tau zoo / siab- qhov kub thiab txias.
Dab tsi yog qhov tsis zoo ntawm 304 stainless hlau?
Qhov tsis zoo ntawm 304 stainless hlau muaj xws li: susceptibility to chloride corrosion (xws li dej hiav txwv), kev ua haujlwm tsis zoo nyob rau hauv qhov chaw muaj zog acid / alkali, qis zog dua lwm cov hlau, susceptibility to stress corrosion cracking, and high cost than carbon steel. Yog li ntawd, nws tsis zoo - haum rau marine, hnyav chemical ib puag ncig, los yog hnyav structural applications.
304 thiab 321 stainless hlau yog ob hom stainless hlau alloys uas txawv nyob rau hauv tshuaj muaj pes tsawg leeg thiab txhua yam khoom. Txawm hais tias ob qho tib si alloys tau siv dav hauv ntau qhov kev lag luam, suav nrog kev lag luam tsheb, lawv qhov sib txawv tseem ceeb ua rau lawv haum rau kev siv sib txawv.
Cov tshuaj muaj pes tsawg leeg ntawm 304 thiab 321 stainless hlau
| Qib | C | Si | Mn | Cr | Ni | S | P | N | Ti |
|---|---|---|---|---|---|---|---|---|---|
| 304 | 0.08 | 1.0 | 2.0 | 18.0-20.0 | 8.0-10.5 | 0.03 | 0.045 | / | / |
| 321 | 0.08 | 1.0 | 2.0 | 17.0-19.0 | 9.0-12.0 | 0.03 | 0.045 | 0.1 | 5C-0.70 |
Lub cev muaj zog ntawm 304 vs 321 Stainless Hlau
| Khoom | 304 Stainless hlau | 321 Stainless hlau |
|---|---|---|
| Crystal Structure | FCC | FCC |
| Tensile zog | Siab | Siab |
| Yield zog | Siab | Siab |
| Qhov ntom | ~8g/cm³ | ~8g/cm³ |
| Melting Point | 1400-1450 degree | 1400-1450 degree |
| Thermal conductivity | 16.2 W/m·K | 16.3 W/m·K |
Chemical Properties ntawm 304 vs 321 Stainless hlau
| Khoom | 304 Stainless hlau | 321 Stainless hlau |
|---|---|---|
| Corrosion Resistance | Zoo | Zoo |
| Intergranular Corrosion | Limited (Tom qab vuam) | Superior (Vim Titanium) |
| Oxidation Resistance | Zoo | Zoo heev |
| Qhov Kev Pab Cuam Siab Tshaj Plaws | ~ 870 degree | ~ 900 degree |
Mechanical Properties ntawm 304 thiab 321 Stainless Hlau
| Property (ntxiv) | Qauv 304 | xwm 321 |
|---|---|---|
| Tensile zog (MPa) | ~500–600 | ~500–600 |
| 0.2% Pov thawj / tawm los (MPa) | ~ 170–275 (feem ntau ≈205) | ~ 170–275 (feem ntau ≈205) |
| Elongation (% hauv 50 mm) | ~40–60 | ~40–60 |
| Impact toughness | Zoo ntawm ambient; khaws cov tawv nqaij ntawm qhov nruab nrab qis | Zoo ib yam li 304; khaws cov toughness ntawm elevated kev pab kub zoo dua vim stabilization |
| Hardness (Brinell / HB) | ~ 100 HB (~ 80-200 nyob ntawm kev ua haujlwm hardening) | ~ 100 HB (zoo ib yam) |
Automotive Applications
304 stainless hlau, vim nws zoo corrosion kuj thiab tsis tshua muaj nqi, feem ntau yog siv nyob rau hauv lub tshuab tso pa, catalytic converters, thiab mufflers . 304 stainless hlau yog haum rau feem ntau automotive daim ntaub ntawv, xws li turbocharger manifolds, muab cov kev khiav hauj lwm kub tsis tshaj 1472℃F (kwv yees li 750 degree).
321 stainless hlau, vim nws siab -kub tsis kam thiab tsis kam mus rau sensitization, feem ntau yog siv nyob rau hauv ultra- siab- kub automotive daim ntawv thov nrog kev khiav hauj lwm kub tshaj 1472℃F (kwv yees li 750 degree) tab sis qis dua 1580℃F (kwv yees li 80). Nws kuj tseem siv tau rau hauv daim ntawv thov vuam qhov twg alloy stabilization kev kho mob yuav tsum tau tiv thaiv rhiab heev thiab intergranular corrosion.
Hauv cov ntsiab lus, ob qho tib si 304 thiab 321 stainless hlau yog dav siv nyob rau hauv kev lag luam tsheb vim lawv zoo heev corrosion kuj, formability, thiab lub zog. Txawm li cas los xij, lawv cov tshuaj muaj pes tsawg leeg thiab cov khoom siv kho tshuab sib txawv, yog li ua rau lawv tsim nyog rau kev siv sib txawv. Thaum 304 stainless hlau feem ntau yog siv rau hauv daim ntawv thov nrog kev khiav hauj lwm kub tsis tshaj 1,472℃F, 321 stainless hlau, vim nws oxidation kuj thiab creep kuj, yog ntau haum rau ultra- siab- daim ntaub ntawv kub.
