1. Q: Lub luag haujlwm tseem ceeb ntawm EN10297-1 20NiCrMoS 2-2 steel raj yog dab tsi?
A:
Khoom siv profile:Seamless precision raj hauv qabTS EN 10297-1, ua los ntawm20 NiCrMoS 2-2(ib leej faj- txhim kho qhov txawv ntawm 20NiCrMo2-2 rau kev txhim kho machinability).
Kev siv tseem ceeb:
Automotive:High-paj kis tau tus mob precision, synchronizer rings (post-carburizing).
Aerospace:Tsis yog - cov khoom siv hluav taws xob tseem ceeb uas yuav tsum tau ua kom muaj zog thiab qaug zog.
Roj & Roj:Laum hlua stabilizers (ntsuas machinability thiab toughness).
Qhov zoo:
Dawb - txiav cov khoom(S: 0.020–0.040%) rau kev ua haujlwm nyuaj.
Case- muaj peev xwm hardening(HRC 58-62 nto hardness).
2. Q: Cov khoom siv dab tsi yuav tsum 20NiCrMoS 2-2 raj ua raws li EN10297-1?
A:
Raws li -Delivered (Annealed):
Tensile zog:950-1150 MPa.
Yield zog (Rp0.2):Ntau dua lossis sib npaug li 750 MPa.
Elongation (A₅):Ntau dua lossis sib npaug li 10%.
Hardness:280–340 IB.
Ncej -Kev kho mob:
Nto hardnessHRC 58–62(carburized), core toughness ~ HRC 30-40.
Lub zog qaug zog: Ntau dua lossis sib npaug ntawm 500 MPa ntawm 10⁶ cycles (polished nto).
3. Q: sulfur (S) cuam tshuam li cas rau kev kho cua sov thiab kev ua haujlwm ntawm 20NiCrMoS 2-2?
A:
Machinability Boost:Cov ntawv sulfurMnS suav nrog, txo cov cuab yeej hnav thaum lub sijhawm machining.
Cov Lus Qhia Txog Kev Kho Hniav Kub:
Carburizing:880-920℃rau 4-10 teev (sulfur muaj qhov cuam tshuam tsawg kawg nkaus ntawm qhov tob).
Quenching:Roj txias (tsis txhob quenching dej los tiv thaiv MnS-induced brittleness).
Kev pauv - tawm:Me ntsis txo qhov cuam tshuam kev cuam tshuam toughness piv rau tus qauv 20NiCrMo2-2.
4. Q: Cov tshuaj muaj pes tsawg leeg ntawm 20NiCrMoS 2-2 yog dab tsi?
A:
Alloy Design (wt.%):
C (0.17–0.23%):Core zog ntawm martensite.
Niag (0.40–0.70%):Txhim kho qis -kub toughness.
Cr (0.40-0.60%):Txhim kho hardenability.
Mos (0.15–0.25%):Mitigates temper embrittlement.
S (0.020–0.040%):Tseem ceeb rau dawb- txiav kev ua tau zoo.
Kev txwv impurity: P Tsawg dua lossis sib npaug li 0.020%, S tswj kom tsis txhob kub tawg.
5. Q: Cov ntawv pov thawj thiab cov ntawv pov thawj zoo li cas?
A:
Kev Ntsuas Cov Txheej Txheem:
NDT:Kev kuaj ultrasonic (EN ISO 17640) + sulfur luam tawm tsom xam (ASTM E1180).
Metallography:Kev ntsuas suav nrog (ASTM E45, Hom A / B Tsawg dua lossis sib npaug rau 2.0).
Cov ntawv pov thawj:
EN 10204 3.2nrog tag nrho traceability.
TIAB SA 16949rau automotive applications.
