Carbide Rotary Burrs (Carbide Rotary Burrs) quality is mainly reflected in the following aspects, these factors have a direct impact on its performance, life and machining effect:
1. Material quality
Purity and particle size of tungsten carbide (WC) particles:
High-quality rotary files use high-purity (≥90%) tungsten carbide powder with grain size controlled between 0.5 and 2 microns to ensure high hardness and wear resistance.
Lower quality rotary files may use tungsten carbide with more impurities, resulting in insufficient hardness or easy chipping.
Binder (Cobalt Co) ratio and distribution:
The cobalt content (usually 6-12%) of high quality rotary files is optimized to ensure a balance of hardness and toughness.
Low quality files may have too much cobalt (resulting in insufficient hardness) or too little (resulting in increased brittleness).
2. Manufacturing process
Sintering process:
High-quality files are sintered using hot is ostatic pressing (HIP) or vacuum sintering techniques to eliminate internal porosity and improve material density and uniformity.
Lower quality files may utilize common sintering processes, resulting in an uneven internal structure that is prone to fracture.
Geometric design and edge shape:
The edge design (e.g., double cutting edge, helical edge) of high-quality rotary files is precisely calculated to ensure high cutting efficiency and smooth chip removal.
Low-quality files may have poorly designed edges, resulting in high cutting resistance and heat buildup.
Dynamic balance control:
High-quality rotary files undergo rigorous dynamic balance testing during the manufacturing process to ensure that there is no vibration at high speeds (>30,000 RPM), which extends tool life.
Lower quality files may have poor dynamic balance, resulting in high vibration and roughness of the machined surface.
3. Coating Technology
Wear resistant coatings:
High quality files may be coated with TiN (Titanium Nitride), TiAlN (Titanium Aluminum Nitride), or diamond coatings, which reduces the coefficient of friction and extends the life of the file by 2-3 times.
Low quality rotary files may be uncoated or unevenly coated, resulting in short life and poor cutting performance.
4. Performance indicators
Hardness:
High-quality rotary files have a hardness of ≥90 HRA (Rockwell hardness), which is close to the theoretical limit for tungsten carbide (94 HRA).
Low quality rotary files may have a hardness below 85 HRA and are prone to wear.
Bending strength:
High-quality files have a flexural strength of ≥3,500 MPa, which ensures that they will not break under heavy loads.
Low-quality files may have a bending strength of less than 2,500 MPa and are prone to chipping or breaking.
Longevity:
High-quality files can last 3-5 times longer per file when cutting 45# steel.
Low-quality files have a short life and require frequent replacement, increasing costs.
5. Application performance
Cutting efficiency:
High quality rotary file cutting resistance is small, high processing efficiency, low surface roughness (Ra ≤ 0.8μm).
Low quality rotary file cutting resistance, low processing efficiency, high surface roughness (Ra>1.6μm).
Applicable materials:
High quality rotary files can process a wide range of materials (e.g. steel, stainless steel, titanium alloys, aluminum alloys, plastics, etc.) with stable performance.
Low-quality rotary files may only be suitable for soft materials and are easily damaged when machining hard materials.
6. Brands and Certifications
Brand:
High-quality rotary files usually come from well-known brands (e.g. NS Tool, Komet, MA Ford) with proven technology and consistent quality.
Low-quality files may come from small factories or unknown brands that lack technical assurance.
Certification:
High-quality files may be certified according to ISO 9001, DIN/ANSI, etc. Some dental files are also subject to FDA or CE certification.
Low-quality files may lack certifications and be unreliable.
7. Price and value for money
High-quality files are more expensive (e.g. industrial grade files).
50
50-200/pc, dental files 50-200/pc, industrial files 50-200/pc.
50-200 per file, dental grade
100
100-500/pc.
(100-500/pc), but long life, stable performance, low long-term use cost.
Low quality rotary files are less expensive, but have a short life, poor performance and high long term cost.
To summarize
Cemented carbide file quality is mainly reflected in the material purity, manufacturing process, coating technology, performance indicators and application performance and other aspects. High-quality files have high hardness, high wear resistance, long life and stable machining performance, suitable for high-precision and high-efficiency machining needs; while low-quality files may have insufficient hardness, short life, poor machining results and other issues. When choosing, it is necessary to match the parameters according to specific application scenarios (material hardness, cutting volume, surface requirements) and prioritize well-known brands and certified products.
