Stainless hlau yog dab tsi?
Cov hlau tsis muaj steel yog cov ntawv luv luv rau "stainless acid-cov hlau tsis muaj zog," hais txog cov chav kawm ntawm cov hlau alloy nrog hlau ua cov khoom siv hauv paus thiab cov ntsiab lus chromium tsis pub tsawg dua 10.5% (los ntawm huab hwm coj). Cov hlau no tuaj yeem hloov kho los ntawm kev ntxiv cov ntsiab lus alloying xws li npib tsib xee, molybdenum, manganese, thiab nitrogen los kho nws cov khoom siv sab hauv thiab cov khoom. Piv txwv li, kev sib koom ua ke nickel rau hauv cov hlau tsis muaj steel txhim kho nws cov corrosion kuj thiab siab -kub kam rau ua. Yog li ntawd, cov khoom siv hlau no pom kev siv dav hauv ntau yam kev lag luam tom qab ua tiav.
Classification ntawm Stainless hlau
Raws li cov microstructure tom qab kev kho cua sov, stainless hlau feem ntau categorized rau hauv tsib hom loj hauv qab no.
Austenitic Stainless hlau
Cov qib ib txwm muaj xws li 304 thiab 316. Hom no muaj qib siab ntawm austenite- tsim cov khoom xws li npib tsib xee, manganese, thiab nitrogen. Nws yog tus cwj pwm los ntawm cov khoom tsis yog- sib nqus, zoo heev ductility thiab toughness, superior weldability, thiab feem ntau zoo corrosion kuj. Txawm li cas los xij, nws tsis tuaj yeem ntxiv dag zog los ntawm kev kho cua sov.
Ferritic Stainless hlau
Ferritic stainless hlau feem ntau siv chromium raws li nws cov khoom alloying thiab nthuav tawm lub cev -centered cubic (BCC) qauv. Qib ib txwm yog 430. Nws yog cov yam ntxwv ntawm cov khoom sib nqus thiab lub zog siab, tab sis pom cov khoom tsis zoo - qhov kub thiab txias, ua rau cov nplej coarsening nyob rau hauv tshav kub- thaj tsam cuam tshuam thaum vuam, thiab qis corrosion kuj piv rau austenitic steel.
Martensitic Stainless hlau
Cov qib ib txwm muaj xws li 410 thiab 420. Lawv muaj lub zog siab thiab tawv, nrog cov khoom siv kho tau los ntawm tempering, tab sis muaj qhov tsis zoo corrosion kuj.
Dej nag-Hardening Stainless hlau
Los ntawm kev ntxiv cov ntsiab lus xws li Cu, Nb, thiab Al, ua raws li kev daws teeb meem thiab nag lossis daus hardening los tsim cov theem ntxiv, cov hlau no sib xyaw ua ke siab zog nrog zoo corrosion kuj. Qib ib txwm yog 17-4PH.
Duplex Stainless hlau
Ua los ntawm ob qho tib si austenitic thiab ferritic theem, xws li 2205. Ua ke lub toughness ntawm austenitic steel nrog lub zog ntawm ferritic steel, muab zoo heev tiv thaiv kev nyuaj siab corrosion cracking.
Cov khoom ntawm Stainless hlau hlau
| Yam khoom | Ntsiab Parameter | Nqe lus piav qhia thiab cov txiaj ntsig zoo |
|---|---|---|
| Mechanical Properties | Tensile zog | Feem ntau nyob rau hauv qhov ntau ntawm 500-1000 MPa, nyob ntawm qib thiab mob. |
| Yield zog | Feem ntau ntawm 200 MPa mus rau ntau dua 550 MPa (qis rau cov hlau austenitic, siab dua rau martensitic thiab nag lossis daus- cov hlau hnyav). | |
| Elongation | Austenitic steels usually >40% yog '; ferritic thiab martensitic steels kuj qis dua. | |
| Hardness | Ntsuas los ntawm Brinell (HB), Rockwell (HRB / HRC), thiab lwm yam, npog ntau yam. | |
| Lub cev muaj zog | Qhov ntom | Kwv yees li ntawm 7.7 - 8.0 g/cm³. |
| Melting Point | Kwv yees li ntawm 1370 - 1450 degree, nyob ntawm seb muaj pes tsawg leeg. | |
| Thermal conductivity | Tus nqi qis, kwv yees li 15-30 W / (m·K), uas yog 1/3 txog 1/2 ntawm carbon hlau. | |
| Coefficient ntawm Thermal Expansion | Siab dua rau austenitic steels (piv txwv li, ~ 17 × 10⁻⁶ / K rau 304), yuav tsum tau saib xyuas rau thermal stress. | |
| Magnetism | Austenitic steels feem ntau tsis yog{0}} sib nqus (tej zaum yuav dhau los ua cov hlau nplaum me ntsis tom qab ua haujlwm); ferritic / martensitic hlau yog hlau nplaum. | |
| Chemical Properties | Corrosion Resistance | Xws li tiv thaiv corrosion tsis zoo, pitting, crevice corrosion, intergranular corrosion, thiab lwm yam. |
| Pitting Resistance Equivalent Number (PREN) | PREN=%Cr + 3.3×%Mo + 16×%N. Tus nqi siab dua feem ntau qhia tau zoo dua pitting kuj. | |
| Manufacturing Properties | Machineability | Nws txawv heev, cuam tshuam los ntawm hardness, toughness, ua hauj lwm -hardening nyiam, thiab additives (xws li, sulfur). |
| Weldability | Feem ntau zoo rau austenitic steels; txo toughness nyob rau hauv HAZ ntawm ferritic steels; martensitic steels xav tau preheating thiab PWHT. | |
| Formability | Austenitic steels muaj cov khoom ua haujlwm txias txias (stamping, sib sib zog nqus nqus); lwm hom kuj tsis zoo. |
Dab tsi yog qhov saum npoo tiav qib rau stainless hlau?
Tom qab kev cai CNC machining, stainless hlau cov ntaub ntawvCustom Stainless hlau qhov chaw. Nws qhov chaw tuaj yeem ua tiav ntau yam kev tshwm sim thiab kev ua haujlwm los ntawm kev dov, polishing, thiab tshuaj kho mob.
Rolled nto: xws li No.1 (kub- dov + annealed), 2B (txias- dov + ci annealed), BA (ci annealed);
Mechanical Polishing: suav nrog Honed (HL), Short-grain (SB), thiab Daim iav (8K).
Stainless hlau vs. Titanium Alloys
| Khoom | Stainless hlau | Titanium alloy |
|---|---|---|
| Qhov ceev (g / cm³) | 7.9 | Kwv yees li 4.5 |
| Lub zog tshwj xeeb | Nruab nrab | Siab heev |
| Corrosion Resistance | Zoo heev (hauv oxidizing media) | Zoo heev (tshwj xeeb tshaj yog nyob rau hauv ib puag ncig chloride ion) |
| Nqi | Tsawg rau nruab nrab | Siab heev |
| Machining nyuaj | Nruab nrab (Kev ua haujlwm nyuaj txawv nyob ntawm qib.) | High (cov cuab yeej hnyav hnyav) |
| Tej kev siv | Cov khoom siv, txhua hnub- siv cov khoom, cov thawv ntim tshuaj | Aerospace, kho mob cog, khoom siv dej hiav txwv |
FAQ
Q: Hauv cov xwm txheej dab tsi tuaj yeem stainless hlau tseem xeb?
A: Stainless hlau yuav corrode nyob rau hauv ib puag ncig uas nws cov zaj duab xis passivation yog tsis tu ncua los yog tsis tuaj yeem kho tus kheej - kho, xws li: xov xwm nrog cov tshuaj chloride ion concentrations siab (seawater), txo cov acid ib puag ncig, crevice structures, los yog galvanic corrosion tshwm sim los ntawm kev sib cuag nrog cov uas tsis yog -hlau.
Q: Yuav ua li cas xaiv ntawm 304 thiab 316 stainless hlau?
A: 304 yog haum rau feem ntau atmospheric, dej tshiab, thiab ib puag ncig tshuaj lom neeg . 316, muaj molybdenum, yog haum rau ib puag ncig nrog chloride ions (xws li, seawater, tshuaj nroj tsuag) los yog qhov siab dua pitting corrosion kuj yuav tsum tau.
Q: Dab tsi yog "kev kho mob passivation"? Nws lub hom phiaj yog dab tsi?
A: Kev kho mob Passivation yog tshuaj lom neeg tshaj tawm - cov txheej txheem ua haujlwm feem ntau siv cov tshuaj nitric acid lossis citric acid kom tshem tawm cov hlau tsis pub dawb los ntawm cov hlau tsis huv (feem ntau yog tshwm sim los ntawm kev sib cuag nrog cov cuab yeej steel thaum tsim khoom) thiab txhawb kev tsim cov khoom ua tiav, zoo li chromium oxide zaj duab xis. Nws lub hom phiaj yog txhawm rau ua kom lub cev muaj zog tiv thaiv corrosion ntawm stainless hlau thiab tiv thaiv nto rusting (stain los ntawm hlau paug).
Q: Ua li cas stainless hlau ua haujlwm ntawm qhov kub thiab txias?
A: Austenitic stainless hlau (piv txwv li, 304, 316) pom zoo heev qis -kub toughness, ua rau lawv haum rau cryogenic ib puag ncig xws li kua nitrogen los yog oxygen. 304 / 316 qib yuav siv tau intermittently qis dua 925℃(1632℃F) thiab tsis tu ncua oxidation qis dua 872℃F (15. Txawm li cas los xij, kev raug ncua ntev ntawm 450-850℃ua rau muaj kev pheej hmoo ntawm carbide nag lossis daus, yuav tsum tau siv qib L-qib lossis qib ruaj khov (piv txwv li, 321).