Weldability ntawm steel: cais. weldability ntawm steel pab pawg neeg

Steel - yog qhov tseem ceeb ntxwv khoom. Nws yog ib tug hlau-cov hlau nrog ib tug cov ntsiab lus ntawm ntau yam impurities. Tag nrho cov Cheebtsam muaj nyob rau hauv nws cov muaj pes tsawg leeg, feem xyuam rau txoj lub zog ntawm cov ingot. Ib tug ntawm cov kev siv technology tshiab yam ntxwv ntawm co yog cov muaj peev xwm tsim tau high-quality welds.

Yam kev txiav txim weldability ntawm steel

Kev luj xyuas ntawm weldability ntawm steel ua los ntawm lub ntsiab index nqi - carbon sib npaug C _eq. Qhov no nyob ntawm coefficient reflecting degree ntawm tus ntawm cov ntsiab lus ntawm cov pa roj carbon thiab lub ntsiab alloying ntsiab nyob rau hauv lub weld yam ntxwv.

Weldability ntawm steel cuam tshuam los ntawm yam nram qab no:

1. Cov pa roj carbon cov ntsiab lus.
2. Qhov muaj kab mob.
3. Lub degree ntawm alloying.
4. Saib microstructure.
5. Environmental tej yam kev mob.
6. hlau thickness.

Qhov tseem tuav parameter yog cov tshuaj muaj pes tsawg leeg.

steels groupings weldability

Muab tag nrho cov yam tseem ceeb, cov weldability ntawm steel muaj ntau yam ntxwv.

Ib suam ntawm steels rau weldability.

• Zoo (ib tug nqi ntawm C _eq ≥0,25%): rau cov uas tsis muaj cov hlau qhov chaw; yog ywj siab ntawm lub thickness ntawm cov khoom, huab cua, lub nyob rau ntawm kev npaj ua hauj lwm.
• Txaus siab (0.25% ≤S _eq ≤0,35%): muaj cov kev txwv rau cov ib puag ncig tej yam kev mob thiab lub lub cheeb ntawm lub qauv yuav tsum tau welded (qhov kub thiab txias rau -5, nyob rau hauv twj ywm huab cua, thickness 20 mm).
• Loo (0.35% ≤S _eq ≤0,45%): rau cov tsim ntawm zoo weld yuav tsum tau rau yav tas los zaub. Nws muaj txhawb rau "smooth" lub austenitic transformation, tus tsim ntawm ruaj lug (ferrite-pearlite, bainitic).
• Txom nyem (P _eq ≥0,45%): tsim ntawm mechanically ruaj khov weld tsis yooj yim sua yam uas tsis tau yav dhau los npaj kub hlau npoo, raws li zoo raws li ib tug tom ntej thaum tshav kub kub kev kho mob ntawm lub welded qauv. Yuav kom tsim tus yam microstructure, ntxiv cov cua kub thiab kua txias.

weldability ntawm steel pawg ua nws yooj yim rau next hauj nta kev hom Vuam hlau-carbon alloys.

Thaum tshav kub kub kev kho mob

Nyob ntawm seb cov pab pawg neeg coj mus rau lub weldability ntawm steels thiab hauj yam ntxwv, tus yam ntxwv ntawm lub welded ob leeg yuav tau tom los ntawm txoj kev successive kub influences. Faib 4 yuav tsum muaj txoj kev tshav kub kev kho mob: hardening, tempering, annealing thiab normalizing.

Feem ntau yog cov hardening thiab tempering rau lub hardness thiab ib txhij weld zog, kev nyuaj siab relieving, tiv thaiv ntes. tempering degree nyob rau hauv cov ntaub ntawv thiab cov kev kawm lub zog.

Thaum tshav kub kub kev kho mob ntawm cov hlau lug nyob rau hauv lub npaj ua hauj lwm yog nqa tawm:

• annealing - mus pab txhawj xeeb nyob rau hauv lub hlau, kom ntseeg tau nws softness thiab pliability;
• yav dhau los rhuab nyob rau hauv thiaj li yuav txo tau qhov kub thiab txias sib txawv.

Zoo tej kev coj vliyaniemi kub tso cai rau koj mus rau:

• los npaj ua hauj lwm yam khoom (tshem tag nrho cov sab hauv txhawj xeeb los ntawm kev sib tsoo cov nplej);
• txo kub gradients rau tus mob khaub thuas hlau;
• txhim kho zoo ntawm cov welded khoom los ntawm tshav kub microstructure kho.

Phau Kho kom raug neeg zog los ntawm kub hloov tej zaum yuav lub zos los yog general. ntug yog rhuab los ntawm cov pa roj los yog hluav taws xob khoom. Yuav kom ua cua sov rau lub tag nrho ib feem thiab tshwj xeeb furnaces yog siv tus txias.

Nyhuv ntawm microstructure rau cov khoom

Lub essence ntawm lub tshav kub kev kho mob dab raws li nyob rau hauv cov yam ntxwv transformations nyob rau hauv lub ingot thiab lawv cov teebmeem nyob rau solidified hlau. Yog li, thaum rhuab mus rau ib tug kub ntawm 727 C nws yog ib tug tov grain austenitic qauv. Cua txias txoj kev txiav txim seb tus hloov dua siab tshiab kev xaiv:

1. Hauv lub cub tawg (ceev 1S / min) - tsim pearlite qauv nrog ib tug hardness ntawm 200 txog HB (Brinell hardness).
2. Nyob rau hauv cov huab cua (10 ° C / min) - sorbitol (ferritic-pearlitic grain) hardness ntawm 300 HB.
3. Roj (100 ° C / min) - troostite (ferrite-cementite microstructure), 400 HB.
4. Dej (1000s / min) - martensite: khoom (600 HB), tab sis lub cev tsis kho acicular qauv.

Vuam compound yuav tsum muaj txaus hardness, muaj zog, zoo kev ntsuas ntawm ductility, txawm li cas los martensitic weld yam ntxwv yog tsis tau. Tsis tshua muaj carbon alloys yog ferritic, ferritic-pearlitic, ferritic-austenitic qauv. Medium-thiab srednelegirovannye steel - pearlite. High-carbon thiab siab - martensitic los yog troostite hais tias nws yog ib qho tseem ceeb coj mus rau lub ferritic-austenitic siab.

Vuam ntawm carbon steels

Weldability yog txiav txim los ntawm tus nqi ntawm cov pa roj carbon steels thiab cov pa roj carbon impurities. Lawv yog cov tau mus hlawv, tig mus rau ib tug gaseous daim ntawv thiab muab cov uas tsis muaj-zoo weld porosity. Sulfur thiab phosphorus yog feeb meej nyob rau hauv cov npoo ntawm cov grains, nce lub fragility ntawm cov qauv. Vuam ntawm cov feem ntau yooj yim to taub, txawm li cas los, yuav tsum tau ib tug neeg mus kom ze.

Carbon steel li ib txwm zoo muab faib ua peb pawg: A, B thiab C. Cov vuam ua hauj lwm yog nqa tawm nrog ib tug hlau ntawm pab pawg neeg B.

Weldability ntawm steel qib VSt1 - VSt4, raws li GOST 380-94, tsiag ntawv los ntawm tsis muaj kev txwv thiab ntxiv uas yuav tsum tau. Vuam paub meej txoj kab uas hla mus rau 40 mm tshwm sim tsis muaj cua sov. Tau ntsuas nyiaj muas: T - siab manganese cov ntsiab lus; KP, ps, sp - "kub", "semi-tua," "calm", ntsig txog.

Me me steel zoo yog sawv cev nrog lub cim qhab nia hundredths carbon feem, cim tias seb thaum cov neeg kawm ntawv ntawm deoxidation thiab manganese cov ntsiab lus (GOST 1050-88): steel 10 (kuj 10PP, 10ps, 10G), 15 (kuj 15kp, 15 ps, 15g), 20 (kuj 20kp, 20ps, 20g).

Yuav ua kom zoo leeg weld pas dej ua ke yuav tsum ua cov txheej txheem ntawm kev tsuas xyaus nrog carbon manganite C thiab Mn.

Txoj kev ntawm vuam:

1. MMA siv tshwj xeeb chiv calcined electrode txoj kab uas hla ntawm 2 mus rau 5 hli. Hom: E38 (rau nruab nrab-lub zog), E42, E46 (zoo zog mus txog 420 MPa), E42A, E46A (rau siab zog complex lug thiab lawv lub lag luam nyob rau hauv tej yam tshwj xeeb). Vuam rods 5 thiab GMM UONI 13/45 ua nyob rau hauv qhov tam sim no. Ua hauj lwm los ntawm lub electrodes CM-7, oma-2, CM-11 yog nqa tawm txhua txhua tam sim no yam ntxwv.
2. Gas welding. Ntau zaus tshaj tsis yog tsis ntshaw, tab sis ua tau. Yog tau siv muab tub lim hlau St-08, St-08A, 08GA-St, St-08GS. Nyias hlau nizkouglerodistyj (d 8mm) welded sab laug txoj kev, tuab (d 8mm) - txoj cai. Tsis zoo Weld zog yog tau tawm los ntawm normalizing los yog annealing.

Vuam cov uas tsis muaj steels khiav lag luam yog tsis muaj ntxiv cua kub. Kom paub meej yooj yim daim ntawv muaj cov tsis muaj kev txwv. Volumetric thiab truss lug tseem ceeb los tiv thaiv los ntawm cov cua. Complex khoom ntshaw kom Weld nyob rau hauv ib tug nroj tsuag ntawm ib tug kub hauv qab no 5 ° C.

Yog li, lub stamp VSt1 - VSt4 steel 10 - steel 20 - zoo weldability, zoo tsis muaj kev txwv, tus qauv yuav tsum tau ib tug neeg xaiv ntawm vuam txoj kev, electrode hom thiab tam sim no muaj cov yam ntxwv.

Medium-thiab high-carbon ntxwv steel

Saturation carbon hlau thiaj li nws muaj peev xwm mus tsim zoo pob qij txha. Cov txheej txheem kub ntawm lub arc roj nplaim teebmeem los yog cov leej faj sau rau ntawm cov npoo ntawm cov nplej, ua rau brittleness, phosphorus - mus txias brittleness. Feem ntau cov feem ntau welded ntaub ntawv doped nrog manganese.

Qhov no muaj xws li cov pa ntxwv steel zoo VSt4, VSt5 (GOST 380-94), zoo 25, 25G, 30, 30G, 35, 35g, 40, 45G (GOSTt 1050-88) sib txawv metallurgy.

Lub essence ntawm lub lag luam yog los txo tus nqi ntawm cov carbon nyob rau hauv lub pas dej ua ke weld hlau saturation therein silicon thiab manganese, kom ntseeg tau pom technology. Nws yog ib qho tseem ceeb los tiv thaiv ntev carbon losses, uas tej zaum yuav ua rau destabilization ntawm tus neeg kho tshuab zog.

Nta vuam steels nrog nruab nrab thiab theem siab carbon cov ntsiab lus:

1. Primal zaub 100-200˚S sawv mus rau lub dav rau 150 mm. Tsuas yog hom VSt4 thiab steel 25 welded tsis muaj ntxiv cua kub. Rau ntawm nruab nrab nrog fee weldability, ua ntej qhov pib ntawm kev ua hauj lwm los tsim ib tug tag nrho cov normalization. Rau siab carbon tsim nyog rau kev npaj mus annealing.
2. Arc vuam yog nqa calcined coated electrodes xws li nyob rau hauv loj los ntawm 3 mus rau 6 hli (TAU-2, UONI-13/55, ELN-7) nyob rau hauv ib qhov tam sim no. tau mus ua hauj lwm nyob rau hauv ib tug nruab nrab flux los yog kev tiv thaiv gases (CO _2, argon).
3. Gas vuam ua carburizing nplaim taws tshuav sijhawm los mus rau yav tas los rhuab rau 200 ° C ntsuas kub ntawm ib tug niaj hnub uas tsis muaj zog mov acetylene.
4. Cov cai thaum tshav kub kub kev kho mob ntawm qhov chaw: quenching thiab tempering los yog cais koj qev los rau txo nrog txhawj xeeb tiv thaiv ntes, softening ntawm martensite thiab tempered troostite lug.
5. Kuj chaw welding yog nqa tawm yam tsis tau muaj kev txwv.

Yog li, medium- rau high-carbon ntxwv steels yog welded nrog zoo tsis muaj kev txwv, nyob rau ntawm ib sab nraud kub ntawm tsis qis tshaj li 5 ° C. Thaum qis kub yuav tsum tau cov cua kub thiab pib ib tug high-zoo thaum tshav kub kub kev kho mob.

Vuam tsawg alloy steels

Alloyed steel - steel yog tias thaum lub sij hawm Melting noo nrog ntau yam co nyob rau hauv thiaj li yuav tau cov yam khoom. Yuav luag tag nrho cov ntawm lawv muaj ib tug zoo ntxim rau cov hardness thiab lub dag lub zog. Chromium thiab npib tsib xee muaj nyob rau hauv lub tshav kub resistant thiab stainless alloys. Vanadium thiab silicon impart elasticity, cov khoom siv rau qhov siv thiab ua springs. Molybdenum, manganese, titanium, txhim khu coj kuj, tungsten - liab hardness. Nyob rau tib lub sij hawm, ib tug zoo ntxim rau cov khoom ntawm qhov chaw, lawv thuam lub weldability ntawm hlau. Nyob rau hauv tas li ntawd, ua rau kom cov neeg kawm ntawv ntawm hardening thiab tsim los ntawm martensitic lug, nrog txhawj xeeb thiab txoj kev pheej hmoo ntawm tawg nyob rau hauv lub nqaws.

Weldability hlau steels raws li sau tseg los ntawm lawv cov tshuaj nyob tus yeees.

Cov uas tsis muaj, tsis tshua muaj-alloyed 2GS, 14G2, 15g, 20g (GOST 4543-71), 15HSND, 16G2AF (GOST 19281-89) yog yuav tsum tau welded. Nyob rau hauv tus txheej txheem tej yam kev mob tsis yuav tsum tau ntxiv cov cua kub thiab kub kev kho mob rau cov kawm tiav ntawm tus txheej txheem. Nyob rau hauv cov ntaub ntawv no, tab sis yog muaj ib co kev txwv:

• Lub nqiam kab kev los ntawm xam thermal hom.
• Ua hauj lwm nqa tawm ntawm ib tug kub tsis qis -10˚S (nyob rau hauv tej yam kev mob ntawm tsawg atmospheric kub, tiam sis tsis hauv qab no -25˚S thov preheating rau 200 ° C).

Tau txoj kev:

• Arc vuam nrog ib tug DC hwj chim ntawm 40 rau 50 A, lub electrodes E55, E50A, E44A.
• Tsis Siv Neeg vuam arc submerged siv muab tub lim hlau 08GA-St, St-10 ha.

Weldability 09G2S 10G2S1 kuj yog ib tug zoo, yuav tsum tau thiab tau txoj kev ua tib yam li ntawd rau alloys 12GS, 14G2, 15g, 20g, 15HSND, 16G2AF. Ib qho tseem ceeb cov yam ntxwv 09G2S alloys 10G2S1 yog tsis muaj yuav tsum tau rau ntug kev npaj rau cov khoom rau 4 cm nyob rau hauv txoj kab uas hla.

Srednelegirovannoj vuam steels

Srednelegirovannye steel 20HGSA, 25HGSA, 35HGSA (GOST 4543-71) tsim ib tug ntau dua kuj mus rau tsim ntawm unstrained nqaws. Lawv muaj ib pab pawg neeg uas txaus siab weldability. Yuav tsum tau pre-cua sov rau kub 150-200˚S, lub multilayered nqaws, quenching thiab tempering ntawm qhov kawg ntawm welding. Embodiments:

• Tus tam sim no lub dag lub zog thiab lub lub cheeb ntawm lub electrode thaum Vuam arc nruj me ntsis xaiv nyob rau hauv lub hlau thickness, noj mus rau hauv tus account uas lub thinner ntug muaj zog raug quenching thaum lub sij hawm ua hauj lwm. Yog li, thaum lub khoom ntawm 2-3 hli txoj kab uas hla tus nqi ntawm cov tam sim no yuav tsum tau tsis pub dhau 50-90 A. Thaum lub thickness ntawm cov npoo ntawm 7-10 hli DC hwj chim ntawm opposite polarity tam sim no yog nce rau 200 A siv 4-6mm electrodes. Siv rods nrog cellulose los yog poov hlau fluor-tiv coatings (18HGSA-St, St-18HMA).
• Nyob rau hauv lub lag luam, shielding roj CO ₂ yog yuav siv St-08G2S hlau Sv-10G2, 10GSMT-St, St-08H3G2SM txoj kab uas hla mus rau 2 hli.

Feem ntau cov ntaub ntawv no yog siv rau Tig vuam txoj kev los yog submerged.

Thaum tshav kub kub-resistant thiab high-zog steels

Vuam nrog thermostable hlau-cov hlau 12MH, 12H1M1F, 25H2M1F, 15H5VF yuav tsum tau nqa tawm nrog preheating rau kub 300-450˚S nrog zaum kawg quench thiab tempered.

• Arc vuam txoj kev cascade clearance multilayer leeg siv calcined coated electrodes UONII 13 / 45MH, CCR-3, 30-63-CL, CL-39.
• Gas mov ntawm acetylene vuam nrog 100 dm ³ / hli siv muab tub lim ntaub ntawv Sv-08HMFA, St-18HMA. Yeeb Nkab kev twb kev txuas yog ua nrog rau yav tas los gas cua kub nyob rau hauv tag nrho cov kev sib koom.

Thaum Vuam high-zog khoom srednelegirovannoj 14H2GM, 14H2GMRB tseem ceeb yuav tsum tau ua los ntawm cov cai xws li rau lub tshav kub-resistant steels, noj mus rau hauv tus account ib co ntawm cov nuances:

• Ua tib zoo tu ntawm npoo thiab siv lub lauj kaub uas tuav.
• Lub siab kub calcination electrode (txog 450˚S).
• Preheating rau 150˚S kom paub meej tuab ntau dua tshaj 2 cm.
• Qeeb txias leeg.

high-hlau steel

Cov kev siv ntawm ib tug tshwj xeeb technology yog tsim nyog thaum Vuam high-hlau steels. Cov no muaj xws li ib tug lossis loj ntau yam ntawm stainless steel, Thaum tshav kub kub-resistant thiab thaum tshav kub kub-resistant alloys, ib txhia ntawm lawv: 09H16N4B, 15H12VNMF, 10H13SYU, 08H17N5MZ, 08H18G8N2T, 03H16N15MZB, 15H17G14A9. Weldability ntawm steel (GOST 5632-72) no belongs rau lub 4 pab pawg neeg.

weldability ntawm steel high-carbon high-Feature:

1. Nws yog tsim nyog los txo qhov nruab nrab tam sim no los ntawm 10-20% vim lawv tsis muaj thermal conductivity.
2. Vuam yuav tsum tau nqa tawm nrog ib tug kis, lub electrodes mus txog 2 hli.
3. Yuav txo tau ntawm phosphorus, ua, sulfur, antimony, o ntawm lub xub ntiag ntawm molybdenum, vanadium, tungsten coated los ntawm kev siv tshwj xeeb tuav.
4. Qhov yuav tsum tau tsim weld mixed microstructure (ferrite + austenite). Qhov no yog qhia ductility ntawm tso hlau thiab nrhiav hauv stresses.
5. Yuav tsum tau cov cua kub npoo Hmo welding. Qhov kub yog xaiv nyob rau hauv lub chav los ntawm 100 mus 300˚S, nyob ntawm seb designs ntawm microstructure.
6. Xaiv cov coated electrodes nyob rau hauv arc vuam yog txhais los ntawm lub hom grain, lub zog thiab kev khiav hauj lwm tej yam kev mob ntawm qhov chaw: rau austenitic steel 12H18N9: UONII 13 / VAW, RLA-7 RLA-14 coated-06H19N9T St, St-02H19N9; rau martensitic steel 20H17N2: UONII 10H17T, IB-B-10 St-08H17T txheej; rau austenitic-ferritic steel 12H21N5T: CL-33 St-08H11V2MF txheej.
7. Thaum acetylene pa roj vuam pub yuav tsum phim tus nqi 70-75 ^dm3 / hli siv muab tub lim hlau - 02H19N9T-St, St-08H19N10B.
8. Tau ua hauj lwm submerged siv VAW-8.

Steel Weldability - txheeb ze parameter. Nws yog nyob ntawm cov tshuaj muaj pes tsawg leeg ntawm cov hlau, nws microstructure thiab lub zog. Yog li lub peev xwm los tsim zoo kev twb kev txuas yuav tau tom ntawm txhob txwm hauj mus kom ze, tshwj xeeb cov khoom thiab kev ua hauj lwm kev mob.