17-4 PABthiab 316L yog ob qho tib si stainless hlau, tab sis lawv muaj nyob rau hauv cov tsev neeg metallurgical sib txawv thiab tsis tshua muaj tseeb hloov rau ib leeg . 316L yog qib austenitic workhorse khoom plig rau corrosion kuj thiab weldability; 17-4PH yog qib los nag-hardening martensitic qib muaj peev xwm ntawm tensile zog ntau dua ob npaug ntawm qhov 316L tuaj yeem ua tiav.
Kev xaiv ntawm lawv yog cov lus nug tiag tiag uas cov cuab yeej tseem ceeb tshaj plaws - lub zog nyoos lossis dav corrosion tsis kam - vim tias cov hlau uas muab txhua qib nws lub zog yog tib yam hlau uas txwv rau lwm qhov. Phau ntawv qhia no muab piv rau 17-4PH thiab 316L ncaj qha nyob rau hauv muaj pes tsawg leeg, lub zog, corrosion kuj, magnetism, thiab fabrication kom meej meej raws nraim thaum txhua qib yog qhov kev xaiv.
17-4PH thiab 316L yog dab tsi, thiab lawv cov qauv metallurgical txawv li cas?
17-4PH yog martensitic nag lossis daus- hardening stainless hlau uas txhim kho nws lub zog los ntawm kev kho cua sov, thaum 316L yog austenitic stainless hlau uas tsis tuaj yeem ntxiv dag zog los ntawm kev kho cua sov txhua - qhov sib txawv ntawm cov qauv no yog lub hauv paus ua rau ze li txhua qhov sib txawv ntawm ob qib.
316L belongs rau tsev neeg austenitic: nws cov ntsiab lus npib tsib xee (10–14%) stabilizes lub ntsej muag -centered cubic crystal qauv ntawm chav tsev kub, uas muab nws zoo ductility, zoo low- kub toughness, thiab tsis yog -magnetic cwj pwm, tab sis critically txhais tau tias nws lub zog tsuas yog nce los ntawm kev ua hauj lwm txias {5} sib txawv ntawm PH. martensitic nag lossis daus- hardening stainless hlau - qhov twg lub cev -centered tetragonal martensitic qauv ntaub ntawv nyob rau hauv txias los ntawm ib tug tov{10}}annealed mob, thiab tom qab aging tshav kub kev kho mob precipitates nplua tooj liab- nplua nuj hais nyob rau hauv lub zog ntawm cov qauv.
Qhov no tsis yog qhov sib txawv me me; nws txhais tau hais tias ob qib ua tiav lawv cov cuab yeej txhais los ntawm cov txheej txheem sib txawv, uas yog vim li cas kev sib piv lawv tsawg dua qhov uas yog "zoo dua" stainless hlau thiab ntau ntxiv txog cov tsev neeg metallurgical twg haum rau daim ntawv thov tiag tiag.
Ua li cas nag lossis daus hardening muab 17-4PH Nws lub zog siab?
17-4PH ua tiav nws lub zog siab los ntawm ob- kauj ruam kev kho cua sov - cov tshuaj annealing ua raws li kev laus - nyob rau hauv uas tooj liab- nplua nuj precipitates nyob thoob plaws hauv martensitic matrix thaum laus, thiab cov nplua, sib npaug ntawm cov precipitates yog dab tsi thaiv cov khoom siv txav mus los.
Cov txheej txheem pib nrog kev daws teeb meem annealing, uas yaj cov ntsiab lus alloying (xws li tooj liab) rau hauv cov khoom sib xws thiab, ntawm qhov txias, hloov cov qauv rau martensite. Hauv qhov xwm txheej no, 17-4PH yog qhov muag muag thiab siv tau. Kev laus tom qab kev kho mob - feem ntau ua nyob rau ntawm qhov kub ntawm li ntawm 480℃mus rau 620℃(900℃F txog 1150℃F) nyob ntawm seb cov khoom uas xav tau kawg - ua rau cov tooj liab yaj los nag los ua cov khoom zoo heev uas tau muab faib thoob plaws hauv martensitic matrix.
Cov precipitates impede lub zog ntawm dislocations nyob rau hauv lub hlau lub crystal qauv, thiab vim dislocation txav yog lub hauv paus mechanism ntawm yas deformation nyob rau hauv hlau, thaiv nws ncaj qha tsub kom cov khoom yield thiab tensile zog. Qhov no yog tib lub hauv paus ntsiab lus ntxiv dag zog siv nyob rau hauv lub hnub nyoog -hardenable aluminium thiab npib tsib xee alloys, thov ntawm no nyob rau hauv ib tug stainless hlau matrix - thiab nws yog kiag li tsis muaj rau 316L, uas nws austenitic qauv tsis undergo hom kev hloov los yog nag lossis daus teb.
Yuav Ua Li Cas 17-4PH thiab 316L Sib Piv hauv Mechanical Strength?
17-4PH nyob rau hauv nws siab tshaj plaws -lub zog tshav kub- kho mob muab kwv yees li ntawm rau mus rau xya npaug ntawm lub zog yield ntawm annealed 316L, thiab txawm nyob rau hauv nws qis-strength tus qauv aging nws tseem ua tau zoo heev outperforms 316L, ua lub zog ib tug loj tshaj plaws thiab tsawg kawg yog tsis meej pem ntawm ob qhov sib txawv.
Kev sib piv ncaj qha thoob plaws 17-4PH kev kho cua sov thiab cov txheej txheem annealed 316L:
|
Qhov xwm txheej |
0.2% Yield zog |
Qhov kawg Tensile Strength |
Elongation |
Hom Siv Case |
|
17-4PH, H900 (lub zog siab tshaj) |
≈ 1170 MPa (170 ksi) |
≈ 1310 MPa (190 ksi) |
≈ 10% |
Lub zog siab tshaj plaws; aerospace fasteners thiab shafts |
|
17-4PH, H1025 (sib npaug) |
≈ 1000 MPa (145 ksi) |
≈ 1070 MPa (155 ksi) |
≈ 12% |
Feem ntau -lub hom phiaj cua sov- kho mob |
|
17-4 PH, H1075 |
≈ 865 MPa (125 ksi) |
≈ 1000 MPa (145 ksi) |
≈ 13% |
Txhim kho toughness nrog tseem - siab zog |
|
17-4PH, H1150 (siab tshaj toughness) |
≈ 725 MPa (105 ksi) |
≈ 930 MPa (135 ksi) |
≈ 16% |
Cov ntawv thov tseem ceeb tshaj qhov toughness thiab ductility tshaj qhov siab tshaj plaws |
|
316l, ua |
≈ 170 MPa (25 ksi) min |
≈ 485 MPa (70 ksi) min |
≈ 40% min |
General corrosion-cov khoom siv ua haujlwm thiab cov txheej txheem tiv taus |
Table 1. Cov neeg sawv cev cov cuab yeej cuab tam sib piv thoob plaws 17-4PH aging tej yam kev mob piv rau annealed 316L. Cov txiaj ntsig yog cov lus piav qhia thiab sib npaug los ntawm cov ntaub ntawv siv tau tshaj tawm; paub meej cov nuj nqis tawm tsam tam sim no ntawm ASTM A564 / A693 lossis cov lus qhia siv tau ua ntej siv rau hauv kev suav tsim.
Qhov kev coj ua zoo tshaj plaws yog tias 17-4PH lub hnub nyoog laus yog nws tus kheej tus qauv tsim, tsis yog tsuas yog kev tsim khoom nthuav dav - H900 muab lub zog siab tshaj plaws ntawm tus nqi ntawm qee qhov toughness thiab ductility, thaum H1150 txi lub zog siab tshaj plaws rau lub ntsiab lus zoo dua toughness, thiab nruab nrab tej yam kev mob xws li H1025} qhov sib npaug ntawm H1025 thiab L10, ib qho txheej txheem annealed cov cuab yeej teeb tsa (hloov tau tsuas yog me me los ntawm kev ua haujlwm txias), uas ua rau nws yooj yim dua tab sis tsis tshua muaj cov khoom siv los ntawm lub zog-tsim standpoint.
Yuav Ua Li Cas 17-4PH thiab 316L Sib piv hauv Corrosion Resistance?
316L muaj lub ntsiab lus zoo dua qub thiab chloride corrosion tsis kam tshaj 17-4PH, feem ntau vim nws cov ntsiab lus molybdenum thiab ntau dua chromium-rau-carbon tshuav nyiaj li cas, ua rau 316L qhov kev xaiv meej thaum twg qhov chaw ua haujlwm - tsis yog tsuas yog cov khoom siv thauj khoom xwb - yog qhov kev txhawj xeeb ntawm kev tsim qauv.
316L's molybdenum tseem tshwj xeeb tshaj yog lub hom phiaj tiv thaiv cov tshuaj chloride-induced pitting thiab crevice corrosion, ib tug mechanism 17-4PH tsis muaj compositional tiv thaiv vim nws tsis txhob txwm molybdenum. 17-4PH's corrosion kuj yog feem ntau suav hais tias piv rau tus qauv 304 {16} stainless hlau nyob rau hauv me me, tab sis kom meej meej nyob rau hauv ib puag ncig chloride tsis kam thiab zoo hauv qab cov qib tshwj xeeb tau tham txog lwm qhov hauv kev siv cov tshuaj chloride siab.
Qhov no yog kev lag luam tseem ceeb- tawm hauv qab ntawm tag nrho 17-4PH piv rau 316L sib piv: 17-4PH's tooj liab ntxiv, uas ua rau nws lub zog los ntawm nag lossis daus hardening, tsis muab tib cov tshuaj chloride kuj tau txais txiaj ntsig uas molybdenum muab hauv 316L-resisting qhov sib txawv ntawm qhov zoo thiab qhov zoo ntawm corrosion. non-overlapping compositional nta es tsis yog ib qib tsuas yog muaj "ntau" zoo alloying zuag qhia tag nrho.
Yog 17-4PH Sib Nqus, thiab Puas Muaj Qhov Tseem Ceeb rau Kev Xaiv Daim Ntawv Thov?
17-4PH yog sib nqus vim nws cov qauv siv lead ua martensitic, thaum 316L feem ntau tsis yog-sib nqus (los yog tsuas yog cov hlau nplaum tsis muaj zog tom qab ua haujlwm txias) vim nws cov qauv austenitic, thiab qhov sib txawv no tseem ceeb hauv txhua daim ntawv thov uas muaj kev cuam tshuam sib nqus, cov khoom siv tsis yog hlau nplaum, lossis cov txheej txheem tshuaj xyuas tshwj xeeb yog qhov tseem ceeb rau kev txiav txim siab.
Cov hlau nplaum hauv cov hlau tsis muaj hlau sib txuas nrog cov qauv siv lead ua: martensitic thiab ferritic stainless hlau, suav nrog 17-4PH, feem ntau sib nqus, thaum qib austenitic zoo li 316L feem ntau tsis yog-sib nqus hauv lawv cov txheej txheem annealed. Qhov no tsis yog qhov xav paub xwb - nws muaj qhov cuam tshuam txog kev tsim qauv hauv cov ntawv thov xws li cov cuab yeej kho mob ze ntawm MRI cov cuab yeej, qee cov khoom siv hluav taws xob lossis cov khoom siv hluav taws xob, thiab cov cuab yeej siv qhov sib nqus cuam tshuam yuav tsum raug txo kom tsawg, tag nrho cov uas feem ntau nyiam 316L lossis lwm qib austenitic tshwj xeeb vim nws cov cwj pwm tsis sib nqus, tsis muaj zog lossis kev xav txog corrosion.
Hloov pauv, kev tshuaj xyuas cov khoom sib nqus, ib qho kev sim thiab tsis zoo rau kev kuaj xyuas qhov chaw thiab nyob ze ntawm -} qhov chaw tsis zoo, muaj feem xyuam rau cov hlau nplaum 17-4PH Cheebtsam tab sis tsis yog rau cov hlau nplaum 316L, uas es tsis txhob cia siab rau txoj hauv kev xws li cov kua dej nkag los yog kev soj ntsuam radiographic.
Ua li cas 17-4PH thiab 316L Sib piv hauv Weldability thiab Fabrication?
316L feem ntau yooj yim dua rau vuam yam tsis muaj kev tshaj tawm tshwj xeeb-welding kev txhawj xeeb txog kev kho cua sov, thaum 17-4PH vuam yuav tsum tau ua tib zoo xav txog cov cua sov- cuam tshuam rau thaj tsam kev hloov pauv tus cwj pwm thiab feem ntau tau txais txiaj ntsig los ntawm kev kho cua sov tom qab vuam kom rov ua tau zoo ib yam ntawm cov khoom sib koom ua ke.
316L's austenitic qauv tsis dhau qhov kev hloov pauv zoo ib yam - tsav cov teeb meem thaum lub sij hawm vuam uas martensitic thiab nag lossis daus - cov qib hardening tuaj yeem ntsib; nws lub ntsiab vuam kev xav yog txo qhov kev pheej hmoo ntawm rhiab heev (chromium carbide nag lossis daus ntawm cov ciam teb), uas nws cov ntsiab lus tsis tshua muaj cov pa roj carbon ntau tau txo qis, ua rau 316L yog qib kev zam txim rau kev sib txuas ntawm ntau yam txheej txheem txheej txheem.
17-4PH's tshav kub- thaj tsam cuam tshuam muaj kev hloov pauv ntawm tib theem uas muab lub hauv paus hlau nws cov khoom, lub ntsiab lus vuam tuaj yeem hloov kho qhov nyuaj thiab cov khoom siv kho tshuab txheeb ze rau niam txiv cov khoom cua sov- kho mob; ntau 17-4PH fabrication txheej txheem yog li hu rau vuam nyob rau hauv cov kev daws teeb meem-annealed mob raws li ib tug tag nrho cov laus thaum tshav kub kub kev kho mob ntawm cov tiav weldment, los yog ib tug ncej-weld aging voj voog, kom rov zoo ib yam khoom thoob plaws hauv lub tivthaiv. Cov txheej txheem ntxiv no tsis yooj yim yog qhov kev xav tau tiag tiag - tsis yog kev xeb lossis lub zog ua lag luam tawm - thaum muab ob qib sib piv rau cov khoom siv welded.
Qib twg koj yuav tsum xaiv rau High-Strength vs Corrosion-Cov ntawv thov tseem ceeb?
17-4PH yog qhov kev xaiv tsim nyog thaum daim ntawv thov thawj qhov yuav tsum tau muaj lub zog siab - rau- qhov hnyav ua haujlwm nyob rau hauv ib puag ncig corrosive, thaum 316L yog qhov kev xaiv tsim nyog thaum dav, txhim khu kev qha corrosion kuj - tshwj xeeb tshaj yog tiv thaiv chlorides - yog qhov yuav tsum tau ua, txawm tias lub txim loj loj.
Cov Lus Qhia Txog Tus Neeg Sawv Cev Rau Kev Thov:
Aerospace fasteners, shafts, thiab structural fittings:17-4PH tau qhia dav dav qhov twg muaj zog siab- rau qhov hnyav piv yog qhov tseem ceeb thiab qhov chaw pabcuam tsis muaj corrosive hnyav.
Roj thiab roj valve Cheebtsam thiab siab -lub zog fittings:17-4PH yog ib qho uas muaj peev xwm ua tau raws li kev tswj hwm, feem ntau nrog kev soj ntsuam ntawm cov tshuaj chloride thiab qaub-kev pabcuam ib puag ncig.
Cov cuab yeej kho mob thiab phais yuav tsum tau muaj zog thiab zoo, tawv tawv:17-4PH lub tshav kub-kho tau lub zog yog nquag leveraged, sib npaug tiv thaiv nws tus nqi nruab nrab corrosion kuj piv rau qib austenitic.
Tshuaj ua cov kav dej, tso tsheb hlau luam, thiab kev txhim kho corrosion- cov cuab yeej tseem ceeb:316L tseem yog tus qauv xaiv, txij li cov kev xav tau ntawm lub zog hauv cov ntawv thov no feem ntau zoo nyob rau hauv qhov uas 316L muab.
Marine, dej hiav txwv, lossis siab -chloride ib puag ncig:316L feem ntau nyiam tshaj 17-4PH vim nws cov molybdenum-tsav pitting tsis kam, tham ntxiv hauv qab no.
17-4PH puas tuaj yeem siv rau hauv chloride lossis Marine Environments?
17-4PH tuaj yeem siv rau hauv cov tshuaj chloride me me tab sis tsis pom zoo los hloov 316L lossis siab dua -cov qib alloy hauv cov tshuaj chloride thiab cov dej hiav txwv hnyav, txij li nws cov corrosion kuj - piv rau tus qauv 304 - yog qhov tseem ceeb hauv qab no dab tsi 316L's ntxiv rau kev tiv thaiv corrosion.
Vim tias 17-4PH lub zog muaj zog (tooj liab rau nag lossis daus hardening) thiab 316L lub zog muaj zog (molybdenum rau cov tshuaj tiv thaiv chloride) tsis sib tshooj, siv 17-4PH nkaus xwb rau nws lub zog kom zoo dua nyob rau hauv ib puag ncig muaj zog chloride tiag tiag ua rau muaj kev tiv thaiv corrosion ntau dua. Nyob rau hauv marginal los yog sib xyaw- yuav tsum tau muaj - qhov twg ob qho tib si lub ntsiab lus muaj zog thiab cov ntsiab lus chloride kuj yuav tsum tau ib txhij - engineers yuav tsum tau soj ntsuam tshwj xeeb los nag-hardening los yog duplex qib formulated nrog ntxiv corrosion-resistant alloying, es tsis yog defaulting rau tus qauv 17-4PH purely ntawm lub zog ntawm nws lub zog ntawm 17-4PH purely ntawm lub zog ntawm lub zog ntawm 1. nws cov corrosion kuj, thaum daim ntawv thov tiag tiag xav tau ob qho tib si.
Cov lus nug nquag
17-4PH puas tuaj yeem rov ua dua los hloov nws lub zog tom qab pib kho cua sov?
Yog lawm, nyob rau hauv kev txwv - 17-4PH feem ntau tuaj yeem rov ua dua- kev daws teeb meem-annealed thiab rov- muaj hnub nyoog mus rau qhov sib txawv yog tias daim ntawv thov yuav tsum tau hloov, txawm hais tias qhov no yuav tsum tau ua kom muaj qhov cub ua kom zoo thiab yog kev txiav txim siab tsim khoom los ntawm txhob txwm tshaj tawm, tsis yog kev hloov kho.
Puas yog 316L muaj cov cua sov- kho kom muaj zog ntxiv rau txhua qhov?
Tsis muaj lub ntsiab lus los nag lossis cua hloov qhov kev xaiv nyuaj rau 316L; nws txoj kev siv dag zog nkaus xwb yog kev ua haujlwm txias (xws li kev kos duab txias lossis dov), uas ua rau kom muaj zog ntawm tus nqi ntawm ductility thiab yog ib qho tseem ceeb sib txawv los ntawm, thiab nyob deb li tsawg tshaj li, 17-4PH lub aging teb.
Puas yog 17-4PH haum rau cov ntawv thov cryogenic?
Feem ntau tsis muaj - martensitic thiab nag lossis daus- cov qib hardening zoo li 17-4PH feem ntau tsis khaws tib qhov kub thiab txias toughness uas austenitic qib zoo li 316L muab, yog li 316L lossis lwm qib austenitic feem ntau yog qhov kev xaiv tsim nyog rau kev ua haujlwm cryogenic.
Qib twg tus nqi ntau dua, 17-4PH lossis 316L?
Tus nqi sib txawv los ntawm kev ua lag luam thiab cov khoom lag luam, tab sis cov qib tsis yog tus nqi zoo heev pom hauv qib super- austenitic lossis nickel alloy; tus nqi sib txawv ntawm 17-4PH thiab 316L feem ntau yog me me piv nrog rau kev sib pauv kev ua haujlwm ntawm lawv, yog li qhov kev txiav txim siab xaiv yuav tsum tau tsav los ntawm kev siv tshuab thiab corrosion feem ntau tsis yog tus nqi ib leeg.
17-4PH thiab 316L tuaj yeem koom ua ke hauv tib lub rooj sib txoos?
Yog lawm, qhov sib txawv ntawm qhov sib txawv ntawm 17-4PH thiab 316L yog qhov ua tau nrog cov txheej txheem hlau tsim nyog thiab cov txheej txheem vuam, txawm hais tias qhov sib koom ua ke cov khoom yuav cuam tshuam cov yam ntxwv txwv ntau dua ntawm txhua qib ntawm qhov chaw tshwj xeeb - qis zog ntawm 316L sab thiab qis dua cov tshuaj chloride tiv thaiv ntawm 17PH-{6} ob qho tib si kev npaj kho cua sov yuav tsum cov qhab nias.
