Long Samarium Cobalt cylinder magnets provide a high-coercivity rare-earth solution for high-temperature and harsh-environment assemblies where conventional Neodymium alternatives suffer irreversible thermal flux loss. Fabricated using high-purity Samarium and Cobalt raw materials, these elongated magnetic components maintain structural and magnetic integrity up to 350°C.
Alloy Classifications: Available in SmCo5 (1:5 series) for high intrinsic coercivity and Sm2Co17 (2:17 series) for maximum energy product at elevated temperatures.
Dimensional Envelope: Diameters from 2 mm to 50 mm with length configurations extending up to 100 mm (aspect ratios exceeding 4:1).
Field Orientation: Standard axial or custom diametrical magnetization profiles aligned via high-tesla magnetic presses.
Technical Specifications
|
Property / Parameter |
SmCo5 (Standard Grade) |
Sm2Co17 (High-Performance Grade) |
|
Typical Grade Examples |
YXG-24, YXG-28 |
YXG-28H, YXG-30H, YXG-32H |
|
Residual Induction (Br) |
9.0 - 10.5 kGs (0.90 - 1.05 T) |
10.5 - 12.0 kGs (1.05 - 1.20 T) |
|
Coercivity (Hcb) |
>= 8.0 kOe (640 kA/m) |
>= 9.5 kOe (756 kA/m) |
|
Intrinsic Coercivity (Hcj) |
>= 15.0 kOe (1194 kA/m) |
>= 25.0 kOe (1989 kA/m) |
|
Max. Energy Product (BH)max |
20 - 28 MGOe (160 - 223 kJ/m3) |
28 - 34 MGOe (223 - 270 kJ/m3) |
|
Max. Operating Temperature |
250°C |
300°C - 350°C |
|
Temp. Coefficient of Br (alpha) |
-0.045% /°C |
-0.030% /°C |
|
Density |
8.4 g/cm3 |
8.4 g/cm3 |
Key Features
Reversible temperature coefficient of Br operates up to 350°C without permanent structural flux degradation.
Cobalt-rich matrix requires no nickel-copper-nickel plating for basic humid or salt-fog deployment.
High Hcj resists demagnetization fields from high-frequency opposing forces.
2-Tesla field pressing prevents magnetic axis deviation across long cylinder spans.
Applications
Aerospace Actuators: High-temperature brushless DC motors and linear actuators.
Traveling-Wave Tubes (TWTs): Microwave amplification devices.
Magnetic Couplings: Hermetically sealed pumps for aggressive chemical fluids.
Downhole Drilling Sensors (MWD): Logging tools exceeding 200°C operating profiles.
Customization
Dimensional Tolerances:
Centerless ground outer diameters (+/- 0.02 mm); length tolerances (+/- 0.05 mm).
Flux Calibration:
Open-circuit Gauss threshold matching (+/- 1% correlation).
Surface Finishes:
Unplated, Ni-Cu-Ni, or Parylene coating for high-vacuum outgassing control.
Delivery State:
Pre-magnetized or unmagnetized (pulse field charging fixtures supplied on request).
Manufacturing & Quality Control
Production Workflow
• Induction Vacuum Melting: Alloy formulation from high-purity ingots.
• Nitrogen Jet Milling: Powder particle size reduction (3 - 5 um).
• Isostatic Pressing: 2-Tesla magnetic field powder alignment.
• Sintering & Aging: Densification at 1100°C - 1200°C followed by multi-stage thermal aging.
• Precision Machining: Diamond-wheel grinding and wire-EDM cutting.
Quality Verification Protocol
• Permeameter Testing: Hysteresis graph verification at 20°C and 200°C (Br, Hcb, (BH)max).
• Laser Micrometer Screening: Concentricity and runout inspection.
• Flux Mapping: Internal micro-void screening (<= 1% flux density drop tolerance).
Packaging & Documentation
High-permeability steel shielding containers complying with IATA DGR limits.
Individual HDPE sleeves with non-magnetic spacers.
Material Test Report (MTR), Certificate of Analysis (CoA), and Rare-Earth MSDS.
FAQ
Hot Tags: long samarium cobalt cylinder magnets, China long samarium cobalt cylinder magnets manufacturers, suppliers, factory, FPC Magnetic Carriers, Magnet for Auto Industry, Samarium Cobalt Disc Magnets, samarium cobalt magnets, Samarium Cobalt Ring Magnets, Square Samarium Cobalt Magnet
