Piastra antiusura Ar
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AR series E Chinese NM series Sono functionally equivalent in terms of durezza, resistenza all'usura, e applicazioni industriali.
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NM series provides a cost-effective alternative for industrial users while maintaining comparable composizione chimica e proprietà meccaniche.
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Selecting the right grade depends on requisiti dell'applicazione, spessore, and availability, but either series can meet high-abrasion industrial needs.
- Descrizione
AR (Resistente all'abrasione) piastre di usura are high-hardness steels designed to withstand extreme wear and impact.
In Cina, the equivalent series is the NM (耐磨) serie, which includes NM400, NM450, NM500, NM550, e NM600.
While both series serve similar purposes, there are differences in composizione chimica, durezza, and mechanical performance.
1. Confronto della composizione chimica
| Grado | C (%) | Mn (%) | Cr (%) | Mo (%) | Altri |
|---|---|---|---|---|---|
| AR400 | 0.2–0,25 | 1.2–1,5 | 0.8–1.2 | 0.2–0,3 | Ni ~0.3 |
| AR450 | 0.25–0,3 | 1.4–1.7 | 0.8–1.3 | 0.2–0,3 | Ni ~0.3 |
| AR500 | 0.3–0.4 | 1.4–1.8 | 0.9–1,5 | 0.2–0.4 | Ni ~0.3 |
| NM400 | 0.18–0.22 | 1.2–1,5 | 0.8–1.1 | 0.15–0,25 | — |
| NM450 | 0.22–0.26 | 1.3–1.6 | 0.8–1.2 | 0.2–0,3 | — |
| NM500 | 0.25–0.32 | 1.4–1.7 | 0.9–1.3 | 0.2–0.35 | — |
Observations:
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Both AR and NM series contain carbonio, manganese, and chromium as key alloying elements.
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AR series may include nickel and slightly higher alloy contents for imported quality control.
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Chinese NM series is produced to GB/T. 24186 standard, ensuring comparable hardness and wear resistance.
2. Mechanical Performance Comparison
| Grado | Durezza (HB) | Resistenza alla trazione (MPa) | Forza di snervamento (MPa) | Resistenza all'impatto (J) |
|---|---|---|---|---|
| AR400 | 400 ± 20 | 850–950 | 550–700 | 25–35 |
| AR450 | 445–475 | 900–1000 | 600–750 | 25–40 |
| AR500 | 500 ± 20 | 950–1100 | 650–800 | 20–35 |
| NM400 | 400 ± 20 | 850–950 | 550–700 | 25–35 |
| NM450 | 440–460 | 900–1000 | 600–750 | 25–40 |
| NM500 | 480–520 | 950–1100 | 650–800 | 20–35 |
Key Takeaways:
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Hardness and tensile properties are very similar between AR and NM grades.
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Both series are suitable for heavy wear applications.
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Slight differences may exist due to raw material sources and heat treatment processes.
3. Applicazioni
| Industria | Serie AR | Serie NM |
|---|---|---|
| Estrazione | Fodere del frantoio, fodera per secchi, tramogge | Same applications |
| Cemento & Costruzione | Lame del miscelatore, scivoli di alimentazione, trasportatori | Same applications |
| Metallurgia | Furnace hoppers, cade, fodere | Same applications |
| Attrezzatura pesante | Benne per escavatori, letti di autocarri con cassone ribaltabile | Same applications |
