ASTM F67 establishes the standard for commercially pure (CP) titanium used in surgical implants, covering unalloyed titanium Grades 1 through 4. Grade 4 (UNS R50700) is the highest strength CP titanium grade, offering an excellent balance of corrosion resistance, biocompatibility, and formability. With tightly controlled interstitial elements (oxygen, nitrogen, hydrogen), this high-purity material is ideal for non-load-bearing medical devices such as pacemaker casings, dental screws, and maxillofacial plates where corrosion resistance and tissue acceptance are critical.
1. Product Specifications & Physical DataGrade 4 CP titanium is available in various mill forms for medical implant manufacturing. The alloy achieves its properties through careful control of interstitial content rather than alloying additions. Available Forms: Sheet, strip, plate, bar, wire, and custom components . Specifications: ASTM F67, ISO 5832-2, UNS R50700 .
| Chemical Composition (Weight %) | Grade 4 Titanium Specification |
|---|
| Titanium (Ti) | 98.6 - 99.0 | | Iron (Fe) | 0.50 max. | | Oxygen (O) | 0.40 max. | | Carbon (C) | 0.10 max. | | Nitrogen (N) | 0.05 max. | | Hydrogen (H) | 0.015 max. |
| Physical Properties | Metric | Imperial |
|---|
| Density | 4.51 g/cm³ | 0.163 lb/in³ | | Melting Point | 1660 - 1670°C | 3020 - 3040°F | | Modulus of Elasticity | 105 - 110 GPa | 15.2 - 16.0 × 10⁶ psi | | Thermal Conductivity (RT) | 16.4 W/m·K | 114 BTU·in/hr·ft²·°F |
| Mechanical Properties (Annealed) | Metric | Imperial |
|---|
| Tensile Strength (min.) | 550 MPa | 80 ksi | | Yield Strength (0.2% offset, min.) | 480 MPa | 70 ksi | | Elongation (min.) | 15% | 15% | | Reduction of Area (min.) | 25% | 25% | | Hardness (Brinell) | 200 - 250 | 200 - 250 |
2. Operating Conditions & Selection CriteriaGrade 4 CP titanium is specified for medical implant applications requiring excellent corrosion resistance and biocompatibility where high strength is not the primary requirement. Biocompatibility: ASTM F67 / ISO 5832-2 approved for surgical implants; excellent tissue acceptance with no adverse reactions . Corrosion Resistance: Outstanding resistance to physiological fluids due to stable passive oxide layer; comparable to higher-grade titanium alloys . Interstitial Control: Tight limits on oxygen (0.40% max), nitrogen (0.05% max), and hydrogen (0.015% max) ensure high purity and prevent embrittlement . Formability: Superior elongation (15% min.) compared to alloyed titanium, allowing complex shaping for patient-specific implants . Non-Magnetic: Fully non-magnetic, ensuring MRI compatibility and patient safety . Service Environment: Ideal for non-load-bearing or low-load applications where extreme strength is unnecessary .
3. Fabrication & Material ComparisonAnnealing: 650-760°C (1200-1400°F) × 10-30 minutes, air cool; relieves stresses and restores ductility . Hot Working: 843-899°C (1550-1650°F); avoid overheating above beta transus (950°C) . Cold Working: Good formability similar to austenitic stainless steel; intermediate annealing may be required for severe deformation . Machining: Requires sharp tools, positive rake angles, and adequate coolant; tendency to gall . Welding: Excellent weldability with inert gas shielding (GTAW); matching filler recommended .
| Material Comparison | Grade 4 CP Ti | Grade 2 CP Ti | Ti-6Al-4V ELI | 316LVM Stainless |
|---|
| Tensile Strength (min.) | 550 MPa | 345 MPa | 860 MPa | 490 MPa | | Yield Strength (min.) | 480 MPa | 275 MPa | 795 MPa | 190 MPa | | Elongation (min.) | 15% | 28% | 10% | 40% | | Modulus of Elasticity | 105-110 GPa | 105-110 GPa | 110 GPa | 193 GPa | | Relative Strength | Highest CP | Moderate CP | Highest (alloy) | Moderate | | Primary Use | Load-bearing CP | General CP | High-load implants | General implants |
4. ApplicationsPacemaker Casings: Corrosion-resistant enclosures for implantable electronic devices Dental Screws: Fixation screws and abutments for dental prosthetics Maxillofacial Plates: Plates and mesh for facial reconstruction Orthopedic Non-Load-Bearing: Plates, screws, and fixation devices in low-stress locations Surgical Instruments: Forceps, retractors, and cutting tools requiring corrosion resistance Cranial Plates: Plates and mesh for skull reconstruction Cryogenic Devices: Components requiring low-temperature toughness
Contact ZYTC Alloy for certified ASTM F67 Grade 4 pure titanium with complete traceability, certificates, and competitive pricing. Available in sheet, plate, bar, wire, and custom forms for medical implant and surgical instrument applications. Email: daisy@zytcsteel.com WhatsApp/WeChat: +86 17335753350 |
