Tungsten Heavy Alloy Boring Bar for Tool - ASTM B777 & Mil-T-21014 Standard

Product Introduction

Our Tungsten Heavy Alloy (WHA) Vibration-Damping Tool Bar is professionally precision-engineered for high-end CNC precision machining, specially optimized for long-overhang boring, deep-hole machining and high-precision turning operations. Different from ordinary steel tool bars and traditional tungsten carbide bars, this product is fabricated from premium W-Ni-Fe tungsten heavy alloy that fully complies with ASTM B777 and US military Mil-T-21014 standards. Featuring ultra-high density, excellent structural rigidity and superior vibration absorption capacity, it effectively suppresses cutting chatter, eliminates machining accuracy deviation caused by excessive tool overhang, and significantly improves workpiece surface finish and overall tool service life.

Conventional steel tool bars are prone to severe elastic deflection and resonant vibration when the length-to-diameter ratio exceeds 4:1, resulting in poor surface roughness, dimensional errors and accelerated tool wear. Our customized tungsten heavy alloy tool bar completely solves this industry pain point, maintaining stable and accurate machining at an overhang ratio of 6:1 to 7:1. It has become an essential precision tool for long-reach and high-precision machining scenarios.

Core Material Advantages

Adopting high-purity 90%–97% W-Ni-Fe tungsten heavy alloy raw materials and mature powder metallurgy sintering process, this material perfectly combines ultra-high density, high elastic modulus and moderate toughness, delivering outstanding vibration damping performance and structural stability:

• Ultra-High Density & Inertia: The density reaches 16.8–18.8 g/cm³, 2.3 times higher than ordinary steel. Excellent mass inertia fundamentally inhibits vibration generation and transmission during cutting.

• High Structural Rigidity: Possesses a higher elastic modulus than steel, effectively reducing micro-deformation and tool deflection under high-speed cutting and heavy-load processing.

• Superior Vibration Damping Performance: The uniform and compact alloy microstructure quickly absorbs and dissipates cutting vibration energy, completely avoiding resonant chatter in long-overhang machining.

• Balanced Mechanical Properties: The optimized nickel-iron bonding phase endows the alloy with excellent comprehensive strength and toughness, resisting cracking and fracture while maintaining stable hardness for continuous heavy-duty machining.

• Excellent Thermal Stability: Low thermal expansion coefficient and stable physical properties ensure consistent machining accuracy without deformation under long-term cutting heat.

Product Performance Features

• Chatter-Free Precision Machining: Effectively suppresses high-frequency cutting vibration and tool flutter, achieving mirror-grade smooth surface finishing for precision workpieces.

• Extended Tool Service Life: Reduces vibration-induced blade impact, friction and abrasion, lowering tool replacement frequency and overall production costs.

• Stable Machining Accuracy: Minimizes dimensional deviation, roundness error and surface defects, ensuring ultra-high precision and repeatability of processed parts.

• Strong Material Adaptability: Suitable for machining various difficult-to-cut materials including stainless steel, titanium alloy, aluminum alloy and die steel.

• Full Customization Support: Non-standard diameters, overall lengths, shank specifications and precision tolerances can be customized strictly according to customer drawings and technical requirements.

• High-Precision Finishing: Adopts ultra-precision grinding treatment with excellent flatness, parallelism and assembly fit, ensuring stable clamping and consistent machining performance.

Standard & Technical Parameters

Executive Standards: Compliant with Mil-T-21014 US Military Specification, ASTM B777-99 / ASTM B777-15 (R2020), ASTM B459-67 (Type II & III) and Chinese GB national product quality standards.

Testing & Verification Standards: Alloy composition tested per ASTM B890-25 (WD-XRF spectrometry); mechanical compression performance tested per ASTM E9-19 (R2025) / GB/T 7314-2017; density tested per ASTM B311; tensile and hardness properties tested per ASTM E8 / ASTM E18.

Typical Physical & Mechanical Properties of Standard Grades

• Optional Alloy Grades: 90W, 92.5W, 93W, 95W, 97W W-Ni-Fe tungsten heavy alloy

• Density Range: 16.85–18.85 g/cm³ (varies by alloy grade)

• Sintered Hardness: HRC 26–35 (stable sintered state)

• Tensile Strength: 689–1050 MPa

• 0.2% Compressive Yield Strength: ≥850 MPa

• Elastic Modulus: 340–360 GPa

Material Grades & Technical Data

Mil-T-21014 / ASTM B459-67 Full Grade Mechanical Data

ASTM B777-99 Official Standard Specification (Metric & Imperial)

Accurate Unit Conversion Reference: 114,000 PSI = 114 ksi ≈ 786 MPa. All technical data is strictly sourced from original military and industrial standard documents, ensuring full authenticity, accuracy and traceability.

Special Compressive Performance of 93W-Ni-Fe Alloy: 0.2% compressive yield strength ranges from 850 MPa to 950 MPa (approximately 123–138 ksi); compressive breaking strength ranges from 1600 MPa to 1800 MPa (approximately 232–261 ksi), featuring excellent compression resistance and structural stability.

Standards & Test Methods

Military Standard: Mil-T-21014 (US Military Specification for Tungsten Heavy Alloy)

Industrial Standards: ASTM B777-99

Application Scenarios

With reliable vibration damping performance and high machining precision, our tungsten heavy alloy tool bars are widely applied in high-precision CNC machining industries, covering aerospace, mold manufacturing, automotive precision parts, hydraulic components, medical equipment and general precision machinery:

• Long-overhang deep-hole boring and turning processing

• Ultra-precision finishing of mold cavities, deep grooves and complex structural parts

• Precision machining of difficult-to-cut materials such as titanium alloy and stainless steel

• High-standard batch production with strict surface roughness and dimensional tolerance requirements

Production & Quality Assurance

All our tungsten heavy alloy vibration-damping tool bars are manufactured via professional powder metallurgy sintering and high-precision mechanical finishing processes, fully compliant with Mil-T-21014 military standard, ASTM B777-99, and Chinese GB quality standards. We implement strict full-process quality management, including raw material incoming inspection, sintering process monitoring, precision machining control and finished product full inspection, to ensure all product density, dimensional accuracy and mechanical properties meet military and industrial grade standards.

To meet global customer procurement and international compliance and environmental compliance requirements, we can provide complete quality certification documents on demand, including third-party material testing certificates, official COA (Certificate of Analysis) and detailed factory inspection reports. All our tungsten heavy alloy boring bars pass RoHS certification and REACH certification, fully complying with EU environmental protection, non-toxic and safety regulations for industrial cutting tools. In terms of dimensional precision control, all precision-machined tool bars are strictly manufactured in accordance with the GB/T 1804 general dimensional tolerance standard, ensuring excellent dimensional consistency, interchangeability and assembly accuracy. All our tungsten heavy alloy boring bars comply with RoHS certification and REACH certification, fully meeting EU environmental protection, non-toxic and safety standards for industrial tools. For dimensional precision control, all precision machined products strictly follow the GB/T 1804 general dimensional tolerance standard, ensuring stable dimensional accuracy, excellent interchangeability and assembly consistency. All products comply with RoHS certification and REACH certification environmental protection standards, meeting EU environmental and safety requirements for industrial machining tools. In terms of dimensional tolerance control, all precision finished boring bars strictly follow the GB/T 1804 general dimensional tolerance standard, ensuring consistent dimensional accuracy and assembly compatibility. Our factory has obtained authoritative international system certifications: ISO 9001 Quality Management System, ISO 45001 Occupational Health and Safety Management System, ISO 18001 Occupational Safety Management System and ISO 13485 Medical Device Quality Management System. We support standardized mass production and customized OEM & ODM services to meet diverse high-standard precision machining and procurement needs worldwide.