1. Q: Dab tsi txhais tau tias EN10297-1 20NiCrMo2-2 raj, thiab qhov twg lawv tau txais kev thuam?
A:
Khoom siv profile:Seamless precision raj hauv qabTS EN 10297-1, ua los ntawm20 NiCrMo2-2(ib siab- zog nickel-chromium-molybdenum alloy steel).
Cov ntawv thov tseem ceeb:
Aerospace:Kev tsaws iav Cheebtsam, actuator shafts (kev qaug zog ua haujlwm Ntau dua lossis sib npaug ntawm 700 MPa ntawm 10⁷ cycles).
Automotive:Siab -kev nyuaj siab drivetrain qhov chaw (xws li, sib txawv zog, turbocharger ncej).
Zog:Roj/gas laum dab tshos yuav tsum toughness ntawm sub-zero kub.
Qhov zoo:Tshwj xeebhardenability(HRC 54–58 tom qab quenching) thiabcuam tshuam tsis kam(Ntau tshaj lossis sib npaug rau 50 J ntawm -40 degree).
2. Q: Cov cuab yeej siv tshuab dab tsi yog EN10297-1 rau 20NiCrMo2-2 raj?
A:
Quenched & Tempered State:
Tensile zog:1000-1200 MPa.
Yield zog (Rp0.2):Ntau dua lossis sib npaug li 850 MPa.
Elongation (A₅):Ntau dua los yog sib npaug li 12% (kom paub meej tias ductility nyob rau hauv dynamic loads).
Hardness:320-380 HB (tub ntxhais); ntog mus rauHRC 58tom qab rooj plaub- hardening.
Fatigue Limit:550-600 MPa (R{2}}, polished nto).
3. Q: Kev kho cua sov zoo li cas rau 20NiCrMo2-2 raj?
A:
Txheej txheem tseem ceeb:
Austenitizing:830–860℃(roj quenching rau tag nrho martensite transformation).
Tempering:550-600℃(sib npaug zog- toughness; siab dua temp → toughness↑).
Case-Kev xaiv Hardening:Carburizing ntawm 900-930℃(qhov tob: 1.0-2.0 mm) + quenching.
Microstructure:Tempered martensite nrog dispersed alloy carbide (SEM{0}}tsim).
4. Q: Dab tsi yog qhov kev tsim qauv alloy tom qab 20NiCrMo2-2 cov khoom xyaw?
A:
Chemical Composition (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 thiab oxidation kuj.
Mos (0.15–0.25%):Tiv thaiv temper embrittlement.
Kev tswj hwm impurity: P/S Tsawg dua lossis sib npaug li 0.015%(ESU-refined rau siab-purity).
5. Q: Cov ntawv pov thawj zoo thiab cov txheej txheem xeem siv li cas?
A:
Kev Xeem Xeem:
NDT:Ultrasonic (EN ISO 17640) + Sib nqus particle (ASTM A275) rau cov kab nrib pleb.
Metallurgical:Ua ntej -austenite grain loj (ASTM E112, Tsawg dua lossis sib npaug rau 5), suav nrog kev ntsuas (ASTM E45, Tsawg dua lossis sib npaug rau 1.5).
Cov ntawv pov thawj:
EN 10204 3.2nrog tag nrho traceability.
Nadcap AC7114rau kev ua raws aerospace.
PEB 2014/68/EUrau cov cuab yeej siv siab.
