Baja Keras
Itu hardfacing layer in hardfacing steel is produced through pengelasan overlay terkontrol, using methods such as GERGAJI, Fcaw, SMAW, or PTA.
By combining a hard, lapisan luar tahan aus dengan a dasar baja yang kuat, hardfacing steel delivers maximum protection in extreme wear and impact environments, menjadikannya ideal untuk pertambangan, semen, kekuatan, dan aplikasi penanganan material.
- Keterangan
Hardfacing steel refers to steel components that have been coated with a hard, lapisan tahan aus melalui pengelasan lapisan luar.
Itu lapisan permukaan keras dramatically increases the abrasi, dampak, and erosion resistance of industrial parts, extending service life in pertambangan, semen, kekuatan, dan aplikasi penanganan material.
Hardfacing Layer Structure
A typical hardfaced steel component has two main layers:
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Lapisan Hamparan (Lapisan Permukaan Keras)
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Terbuat dari baja paduan tinggi, kromium karbida, atau paduan berbasis kobalt.
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Kekerasan: 50–65 HRC depending on the material.
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Fungsi: Protects against sliding, dampak, and erosive wear.
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Lapisan Baja Dasar
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Biasanya baja ringan (Q235), AR/NM memakai baja, atau baja struktural.
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Menyediakan kekerasan, resistensi dampak, dan dukungan struktural.
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Hardfacing Welding Processes
Several welding techniques are used to deposit the hardfacing layer:
| Proses | Keterangan | Keuntungan |
|---|---|---|
| Pengelasan Busur Terendam (GERGAJI) | Large-scale welding with chromium carbide or hardfacing wires | Tingkat deposisi yang tinggi, uniform layer thickness |
| Pengelasan Busur Inti Fluks (Fcaw) | Uses flux-cored wires with hard particles | Fleksibel, suitable for medium and small parts |
| Pengelasan Busur Logam Terlindung (SMAW) | Pengelasan manual dengan batang hardfacing | Sederhana, ideal for repairs or field work |
| Busur yang Ditransfer Plasma (PTA) | High-energy plasma weld deposits powder overlay | Kekerasan yang sangat tinggi, minimal dilution, ketahanan aus yang sangat baik |
Key Considerations in Hardfacing
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Ketebalan overlay
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Khas 3–20 mm depending on wear conditions.
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Multi-pass welding may be used to build up the desired thickness.
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Pemanasan awal & Interpass Temperature
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Thick steel components may require pemanasan awal (150–250°C) untuk mencegah retak.
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Interpass temperature control ensures uniform hardness and minimal residual stress.
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Dilution Control
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Maintaining pengenceran rendah (≤10–15%) between the overlay and base steel is critical to preserve hardness.
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Perlakuan Panas Pasca Pengelasan
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Stress relief at 150–200°C may be applied.
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Mengurangi residual stresses and ensures dimensional stability.
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Penyelesaian Permukaan
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Grinding or shot blasting removes weld spatter and uneven surfaces.
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Memastikan consistent wear resistance and smooth operation.
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Typical Applications of Hardfacing Steel
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Pertambangan: Lapisan penghancur, tepi ember, pelat palu
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Semen & Konkret: peluncuran bubur, pisau pengaduk, konveyor sekrup
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Pembangkit Listrik: Coal chutes, ash handling equipment
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Daur ulang & Penanganan Material: Penghancur, permukaan benturan, liner konveyor
Advantages of Hardfacing Layer
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Ketahanan Aus Ekstrim: Protects equipment from sliding and impact abrasion
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Kehidupan Layanan yang Diperpanjang: Mengurangi waktu henti dan biaya pemeliharaan
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Customized Overlay: Thickness and alloy composition tailored to operating conditions
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Ketangguhan Dampak: Steel base absorbs shocks while the overlay resists wear
