Si vous êtes ingénieur, acheteur, ou fabricant à la recherche d'un acier à teneur moyenne en carbone fiable, 1045 cold rolled steel is likely on your radar. Ce matériau polyvalent équilibre la résistance, usinabilité, et le coût, ce qui en fait un excellent choix pour tout, des arbres aux pièces automobiles. Dans ce guide, nous allons décomposer ses propriétés clés, conseils de fabrication, utilisations industrielles, and how to source it smartly.
1. Propriétés des matériaux & Notes: What Makes 1045 Cold Rolled Steel Unique?
1045 cold rolled steel is a medium-carbon alloy defined by its precise chemical composition and global equivalent grades. Commençons par les bases:
Composition chimique
The “45” in 1045 refers to itscarbon content (0.45%) —a sweet spot that gives it more strength than low-carbon steels (comme 1018) without sacrificing too much machinability. Here’s a full breakdown:
| Élément | Gamme de contenu | Rôle |
|---|---|---|
| Carbone (C) | 0.42–0.48% | Boosts strength and hardness |
| Manganèse (Mn) | 0.60–0.90% | Improves tensile strength and toughness |
| Phosphore (P.) | Max 0.035% | Controlled to avoid brittleness |
| Soufre (S) | Max 0.040% | Enhances machinability (coupe libre) |
Global Equivalent Grades
If you source from international suppliers, you’ll encounter these alternatives toAISI 1045 CR:
- DEPUIS 1.1191 (Allemagne)
- JIS S45C (Japan)
- GB 45# (Chine)
- EN C45E (Europe)
- UNS G10450 (USA)
Key Material Traits
- Microstructure: Bien ferrite-pearlite mix (from cold rolling), which improves surface finish and dimensional accuracy.
- Densité: Standard for steel at 7.85 g/cm³ —easy to calculate weight for design.
- Indice d'usinabilité: ~70 (contre. 100 pour 1215 acier)—excellent for turning, fraisage, and drilling without excessive tool wear.
- Weldability: Moderate—preheating to 200–300°C (392–572°F) empêche les fissures, making it suitable for welded machine parts.
2. Mécanique & Propriétés physiques: Data You Can Trust for Design
When engineering components like axles or bolts, you need precise mechanical data. Below is a table of typical properties forcold rolled 1045 acier (annealed condition):
| Propriété | Valeur | Test Standard |
|---|---|---|
| Résistance à la traction | 600–700 MPa (87–102 ksi) | ASTM A370 |
| Limite d'élasticité | 420–500 MPa (61–73 ksi) | ASTM A370 |
| Elongation at Break | 15–20% | ASTM A370 |
| Reduction of Area | 40–50% | ASTM A370 |
| Dureté (HRB) | 80–90 | ASTM E18 |
| Dureté (CRH) | 17–22 (after quenching) | ASTM E18 |
| Modulus of Elasticity | 200 GPa (29,000 ksi) | ASTM E111 |
| Poisson’s Ratio | 0.29 | ASTM E111 |
Real-World Example
A manufacturer ofhydraulic piston rods utilise 1045 CR because its high tensile strength (650 MPa) resists bending under pressure, while its lowresidual stresses after cold rolling ensures the rods stay straight during use. Leétat de surface (Ra 0.8–1.6 μm) also reduces friction with seals—extending the rod’s lifespan by 30% compared to hot-rolled alternatives.
Other Critical Traits
- Résistance aux chocs: 20–30 J at room temperature (ASTM A370)—enough for non-extreme environments like agricultural machinery.
- Fatigue Strength: 250–300 MPa (36–44 ksi) for 10^6 cycles—ideal for rotating parts like gears and pinions.
- Tolérances dimensionnelles: Typiquement h9/h11 (OIN 286)—critical for parts that need tight fits, such as jigs and fixtures.
3. Traitement & Fabrication Techniques: How to Work With 1045 Acier laminé à froid
1045 cold rolled steel responds well to most fabrication methods, but proper techniques ensure optimal results. Here’s what you need to know:
Primary Fabrication Methods
- Cold Rolling: The initial process that creates a smooth surface and tight tolerances. Unlike hot rolling, it’s done at room temperature—no scaling or warping.
- Usinage:
- Turning/Milling: Utiliser de l'acier rapide (HSS) or carbide tools with cutting speeds of 15–25 m/min (50–80 ft/min) for best results.
- Forage: Pre-drill small pilot holes to prevent work hardening (common in medium-carbon steels).
- Traitement thermique:
- Recuit: Heat to 815–845°C (1500–1550°F), hold 1–2 hours, cool slowly. Softens the steel for easier machining.
- Trempe & Trempe: Heat to 830–860°C (1525–1580°F), quench in water/oil, then temper at 200–600°C (392–1112°F). Increases hardness to HRC 30–40 for high-wear parts like mining tools.
- Stress Relieving: Heat to 550–650°C (1022–1202°F) to reduce residual stresses after welding or machining.
Finition des surfaces & Revêtements
- Affûtage: Centerless grinding achieves Ra 0.4 μm for precision parts like spindles.
- Revêtements: Zinc plating (pour la résistance à la corrosion) or black oxide (pour l'esthétique) are common. A manufacturer of attaches uses zinc-plated 1045 CR bolts for outdoor construction—they last 5+ years without rust.
4. Applications & Secteurs: Where 1045 Cold Rolled Steel Shines
Thanks to its balanced properties, 1045 cold rolled steel is used across industries. Voici les applications les plus courantes, with real-world use cases:
| Industrie | Applications | Why 1045 CR? |
|---|---|---|
| Automobile | Arbres, engrenages, bolts | Haute résistance + bonne soudabilité |
| Construction Equipment | Hydraulic piston rods, conveyor rolls | Resists bending + porter |
| Agriculture | Tractor axles, plow parts | Toughness for heavy loads |
| Machinerie | Gabarits, luminaires, die holders | Tolérances serrées + usinabilité |
| Robotique | Arm components, attaches | Stabilité dimensionnelle |
Étude de cas: Automotive Gears
A leading car manufacturer switched from 1018 steel to1045 cold rolled bar for transmission gears. Le 0.45% carbon content increased gear hardness by 25%, reducing wear and extending the transmission’s lifespan from 150,000 à 200,000 kilomètres. The cold-rolled surface also eliminated the need for extra grinding—cutting production time by 10%.
5. Normes, Certifications & Contrôle de qualité: Ensuring You Get High-Quality Material
To avoid subpar steel, always check for compliance with global standards and quality certifications:
Key Standards
- ASTM A108: Specifies cold-finished carbon steel bars (includes 1045 cold finish).
- ASTM A29: Covers hot-rolled carbon steel bars (base material for cold rolling).
- DANS 10277: European standard for cold-finished steel (includes EN C45E).
- JIS G4051: Japanese standard for carbon steel for mechanical structures (includes JIS S45C).
Certifications de qualité
- MTR (Mill Test Report): Verifies chemical composition and mechanical properties—ask suppliers for this.
- DANS 10204 3.1: A third-party certificate confirming compliance (critical for aerospace or medical parts).
- OIN 9001: Ensures the supplier follows quality management systems.
- RoHS/REACH Compliance: Mandatory for parts sold in the EU (restricts hazardous substances).
Quality Control Tests
- Ultrasonic Testing: Detects internal defects (par ex., fissures) in thick 1045 cold rolled plate.
- Magnetic Particle Inspection: Finds surface cracks in shafts or axles.
- Dimensional Checks: Vérifier straightness limits (maximum 1 mm/m) et tolérances (per ASTM A484).
6. Marché & Procurement Insights: How to Source 1045 Acier laminé à froid
Approvisionnement1045 cold rolled steel wisely saves time and money. Below are key tips for buyers:
Tarifs & MOQ
- Price per kg: $1.50–$3.00 (varie selon la taille, quantité, and region). Par exemple, un 1045 cold rolled bar (20mm diamètre) costs ~$2.20/kg in the USA, contre. ~$1.80/kg from Chinese suppliers.
- Price per meter: $5.00–$15.00 (depends on diameter/thickness).
- MOQ (Minimum Order Quantity): Most suppliers require 100–500 kg for standard sizes; custom cuts may have higher MOQs.
Global Suppliers
- USA: Nucor, Steel Dynamics (domestic mills with fast lead times: 1–2 semaines).
- Chine: Baosteel, Wuhan Iron and Steel (low-cost options, lead times: 3–4 semaines).
- Europe: ArcelorMittal, Thyssenkrupp (compliant with EN standards, lead times: 2–3 semaines).
Sourcing Tips
- Stock Sizes: Choose standard sizes (par ex., 10mm, 15mm, 20mm bars) to avoid custom fees.
- Conditionnement: Ask for anti-rust oil and export packaging (wooden crates) to prevent damage during shipping.
- Incoterms: Utiliser FOB (Free On Board) for cost control, ou CIF (Coût, Insurance, Freight) for hassle-free delivery.
- Tariff Codes: HS 7228.50 (cold-rolled carbon steel bars) —check local tariffs to avoid surprises.
Yigu Technology’s Perspective
Chez Yigu Technologie, nous recommandons1045 cold rolled steel for customers needing a cost-effective, high-performance medium-carbon solution. Its machinability and strength make it ideal for custom machine components—we’ve used it to manufacture precisionshafts and die holders pour les clients automobiles, reducing their production costs by 15% contre. using higher-grade steels. We also prioritize suppliers withDANS 10204 3.1 certification to ensure consistency, and offer custom cut-to-length services to meet small-batch needs.
FAQ
- Is 1045 cold rolled steel suitable for outdoor applications?
Oui, but it requires corrosion protection (par ex., zinc plating or painting). Uncoated 1045 CR will rust in moist environments, so we recommend coatings for outdoor parts like construction fasteners. - Can 1045 cold rolled steel be heat-treated to increase hardness?
Absolument. Quenching and tempering can raise its hardness to HRC 30–40, making it suitable for high-wear parts like gears and mining tools. Recuit, par contre, softens it for easier machining. - What’s the difference between 1045 cold rolled and hot-rolled steel?
Cold-rolled 1045 has a smoother surface (Ra 0.8–1.6 μm), tolérances plus strictes (h9/h11), and higher strength. Hot-rolled 1045 is cheaper but has a rough surface and looser tolerances—best for non-precision parts like structural brackets.