1.7220 (34CrMo4) & SCM435 Steel CNC Machining

When global engineering drawings call for DIN 1.7220 (34CrMo4) or JIS SCM435, they are specifying a premium Chromium-Molybdenum alloy steel designed for high tensile applications. Slightly lower in carbon than 4140, this grade offers an excellent balance of strength, toughness, and wear resistance, particularly after Quenching and Tempering (Q&T). At JUCHENG, we specialize in processing these specific international grades. Whether you need high-strength automotive fasteners, gas cylinder components, or power transmission shafts, we ensure the material properties meet the strict requirements of European and Japanese standards.

1.7220 (34CrMo4) & SCM435 Steel CNC Machining
1.7220 (34CrMo4) / SCM435 Alloy Steel Machining
When global engineering drawings call for DIN 1.7220 (34CrMo4) or JIS SCM435, they are specifying a premium Chromium-Molybdenum alloy steel designed for high tensile applications. Slightly lower in carbon than 4140, this grade offers an excellent balance of strength, toughness, and wear resistance, particularly after Quenching and Tempering (Q&T). At JUCHENG, we specialize in processing these specific international grades. Whether you need high-strength automotive fasteners, gas cylinder components, or power transmission shafts, we ensure the material properties meet the strict requirements of European and Japanese standards.
1.7220 Alloy Steel

JUCHENG's 1.7220/SCM435 Fabrication Capabilities

We provide specialized processing for high-stress components:
  • Filettatura di Precisione: Since SCM435 is the standard for high-strength bolts (Grade 10.9/12.9), we offer thread rolling and CNC single-point threading to ensure Class 3A/6g thread fits.
  • Heat Treatment (Q&T): We perform precise quenching and tempering to achieve the desired mechanical properties (typically 900-1100 MPa tensile strength) while maintaining toughness.
  • Hard Turning: For parts hardened after rough machining, we utilize CBN tooling to finish critical diameters to H6 tolerances without grinding.
  • Surface Protection: We provide Phosphate Coating (Parkerizing), Dacromet, or Zinc-Nickel plating, which are standard finishes for automotive fasteners made from this material.

Advantages of CNC Machining 1.7220/SCM435

Vantaggio Descrizione dettagliata Beneficio principale
High Static & Dynamic Strength Excellent response to heat treatment. Capable of withstanding heavy static loads and dynamic shocks (axles/bolts).
Superior Toughness Slightly better ductility and impact resistance than 4140 due to lower carbon. Reduces the risk of brittle failure in safety-critical parts like steering knuckles.
Consistent Hardenability The Cr-Mo content ensures uniform hardness penetration. Reliable mechanical properties throughout the cross-section of shafts and bolts.
Cold Formability In the annealed state, it has good plasticity. Suitable for parts requiring cold heading or upsetting before machining.
Resistenza all'usura Can be surface hardened (Induction/Nitriding). Extends the life of gears and splines.

Parametri tecnici e norme sui materiali

We stock materials compliant with both European and Asian standards:
Categoria del Grado Specifica Caratteristiche e usi ideali
DIN 1.7220 / 34CrMo4 European Standard Characteristics: Chromium-Molybdenum tempering steel. High toughness in the QT condition. Widely used in the German automotive industry.
Uses: High-pressure gas cylinders, axle arms, connecting rods, pinions.
JIS SCM435 Japanese Standard Characteristics: The equivalent Japanese grade. The gold standard for high-strength bolts and automotive suspension parts.
Uses: Grade 10.9 / 12.9 Bolts, engine components, motorcycle frames.
Condition +QT Quenched & Tempered Characteristics: Heat treated to obtain high tensile strength (e.g., 900-1100 MPa) before or after machining.
Uses: Final functional parts ready for load.

CNC Machining Guidelines for SCM435

  • Lavorabilità: In the annealed condition, machinability is good (similar to 4140). In the Q&T condition (approx. 30 HRC), it requires rigid setups and coated carbide tools.
  • Saldatura: Requires pre-heating (200-300°C) and post-weld stress relief to prevent cracking in the HAZ (Heat Affected Zone).
  • Distortion: Long shafts made from SCM435 can distort during heat treatment. We leave grinding allowance or use stress-relieved stock to mitigate this.
  • Induction Hardening: This material is excellent for induction hardening specific areas (like bearing journals) to 50-55 HRC while keeping the core tough.

Scenari Applicativi

  • Automotive: Cylinder head bolts, crankshafts, steering arms, stabilizers.
  • Elementi di fissaggio: High-strength socket head cap screws (SHCS), studs, anchors.
  • Energy: Seamless gas cylinders (CNG tanks), pressure vessel necks.
  • Heavy Machinery: Drive shafts, conveyor pins, high-stress gears.

Tabella delle Proprietà Fisiche

Typical mechanical properties in Quenched & Tempered (+QT) condition:
Proprietà 1.7220 / SCM435 (+QT) 1045 Carbon Steel Unità
Densità 7.85 7.87 g/cm³
Resistenza a Trazione 900 - 1100 570 - 700 MPa
Carico di Snervamento 650 - 900 310 - 450 MPa
Allungamento 10 - 14 16 %
Durezza 28 - 34 HRC 170 - 210 HB -
Impact Energy (KV) > 35 Basso Joules
 
Jucheng Precision Factory
Richiedi il tuo DFM e Preventivo – Carica i tuoi Disegni
ㆍInserisci i tuoi requisiti e carica il tuo file 2D e 3D, ti forniremo il preventivo e il DFM entro 24 ore.
ㆍTipi di file: STEP, STP, IGES, IGS, SLDPRT, 3DM, SAT, X_T, DWG, DXF, STL, PDF, ZIP e altri. Dimensione file: < 128 MB Dimensione pezzo: < 1500*1500*1500 mm
ㆍPrivacy: Rispettiamo la tua privacy. Qui puoi trovare un esempio di accordo di non divulgazione. Inviando questo modulo, accetti i nostri termini e condizioni e la politica sulla privacy.