| Category | Parameter | Value / Specification |
|---|---|---|
| Alloy Designation | Material | NiCr (Nickel-Chromium alloy) |
| Typical Applications | Applications | • Orthopedic implants • Metal crowns for dental porcelain-fused-to-metal (PFM) restorations • Removable partial denture frameworks • Clasps |
| Applicable Processes | Manufacturing Process | SLM (Selective Laser Melting) |
| Chemical Composition (wt.%) | Ni | 55.7–64.2 |
| Cr | 24–28 | |
| Mo | 11–13 | |
| Si | 0.8–1.8 | |
| Nb | ≤ 1.0 | |
| C | ≤ 0.2 | |
| Be | < 0.02 | |
| Cd | < 0.02 | |
| Pb | < 0.02 | |
| P | < 0.015 | |
| O | < 0.08 | |
| S | < 0.015 | |
| N | < 0.15 | |
| H | < 0.1 | |
| Fe | < 0.5 | |
| — | / (not specified) | |
| Physical Properties | Particle Size Range (µm) | D10 ≥ 12; D50: 25–40; D90 ≤ 65 |
| Sphericity | ≥ 0.85 | |
| Apparent Density (g/cm³) | ≥ 4.4 | |
| Tap Density (g/cm³) | ≥ 5 | |
| Flowability (s/50g) | ≤ 25 | |
| Mechanical Properties (Heat-Treated) | Porosity | ≤ 1% |
| 0.2% Proof Strength (MPa) | ≥ 600 | |
| Elongation (%) | ≥ 10 | |
| Young’s Modulus (GPa) | ≥ 150 | |
| Hardness (HV) | ≥ 300 | |
| As-Formed Density (g/cm³) | 8.5 | |
| Surface Roughness (Ra, µm) | ≤ 2.5 |
Note: All values are typical specifications for NiCr powder intended for SLM additive manufacturing in dental and medical applications. “As-Formed Density” refers to the density of the part after SLM processing (without post-processing like HIP). Ra = arithmetic average roughness.
1. Advantages and Features of This NiCr Alloy Powder
Based on its technical specifications, NiCr Alloy Powder offers distinct advantages for SLM applications, summarized as follows:
1.1 Optimized for Dental Applications
- Biocompatibility Focus: Engineered specifically for dental markets, meeting stringent safety requirements for intraoral devices like porcelain-fused-to-metal (PFM) crowns and removable partial denture frameworks.
- Proven Clinical Track Record: The NiCr composition has a long history of successful use in non-load-bearing dental restorations, demonstrating excellent biocompatibility and corrosion resistance in the oral environment.
1.2 Excellent SLM Processability
- High Flowability & Density: With a flowability of ≤25 s/50g, apparent density ≥4.0 g/cm³, and tap density ≥4.5 g/cm³, the powder ensures even spreading during the SLM process, minimizing porosity and resulting in high-density printed parts.
- Controlled Particle Size Distribution: The D50 range of 25–40 μm (with D10 ≥12 μm and D90 ≤65 μm) is ideal for achieving fine-feature resolution in SLM, enabling the production of intricate dental frameworks and clasps.
- High Sphericity (≥0.85): Ensures consistent powder bed packing and stable melt pool dynamics, critical for repeatable mechanical properties in additively manufactured parts.
1.3 Robust Mechanical Performance
- High Strength & Corrosion Resistance: The synergistic effect of Cr and Mo provides high strength and exceptional corrosion resistance, crucial for long-lasting dental prosthetics exposed to saliva and food acids.
- Good Fatigue Resistance: The material exhibits good fatigue strength, essential for components subjected to cyclic masticatory loads over their service life.
1.4 Stable Physical Properties
- Consistent Elastic Modulus: A Young’s modulus of approximately 150 GPa provides the necessary stiffness for structural support in dental frameworks without being overly rigid.
1.5 High Purity & Compositional Control
- Low Interstitial Impurities: Strict limits on oxygen (<0.08%), nitrogen (<0.15%), and hydrogen (<0.1%) minimize oxide inclusions and gas porosity in printed parts, enhancing fatigue resistance and biocompatibility.
- Balanced Alloying Elements: The precise Cr (24–28%) and Mo (11–13%) content ensures optimal corrosion resistance in physiological environments and stabilizes the microstructure during SLM processing. Harmful elements like Be, Cd, and Pb are strictly controlled to <0.02%.
In summary, NiCr Alloy Powder is a dental-grade, SLM-optimized alloy that combines reliable processability (flowability, particle size), robust mechanical performance (strength, corrosion resistance), and proven biocompatibility. It is specifically tailored for demanding additive manufacturing applications in the dental sector, where precision, safety, and long-term functionality are paramount.
2. NiCr Alloy Powder Material Overview
NiCr Alloy Powder is a nickel-chromium-molybdenum alloy powder specifically designed for Selective Laser Melting (SLM) additive manufacturing processes. Classified as a biocompatible dental-grade metal, this material adheres to international standards for dental prosthetics. Through precise compositional control and advanced powder preparation techniques, it ensures that printed components meet rigorous clinical requirements for mechanical properties and corrosion resistance, serving as a foundational material for personalized dental device manufacturing.
2.1 Chemical Composition Characteristics
The alloy uses nickel as the base (55.7–64.2 wt.%), with chromium content controlled at 24–28 wt.% to form a dense, passive chromium oxide film, providing excellent corrosion resistance and biocompatibility. Molybdenum (11–13 wt.%) contributes to solid solution strengthening, significantly enhancing material strength and corrosion resistance. Carbon is limited to ≤0.2 wt.% to control carbide formation, while silicon (0.8–1.8 wt.%) aids in deoxidation. Harmful impurities are strictly controlled: beryllium (Be), cadmium (Cd), and lead (Pb) are all <0.02%, and interstitial elements oxygen, nitrogen, and hydrogen are kept below 0.08%, 0.15%, and 0.1% respectively, ensuring the density and biological safety of printed parts.
2.2 Powder Characteristics
NiCr powder features a highly spherical morphology (sphericity ≥0.85) with a particle size distribution optimized for SLM processing: D10 ≥12 μm, D50 = 25–40 μm, and D90 ≤65 μm, ensuring uniform powder spreading and fine feature resolution. It exhibits an apparent density of ≥4.0 g/cm³, tap density of ≥4.5 g/cm³, and flowability of ≤25 s/50g, demonstrating superior flow and packing behavior that effectively reduces defects during spreading, laying the physical foundation for high-density, high-quality printed components.
3. Technical Advantages
The core advantage of NiCr powder lies in its “process-performance-application” integration for dental devices. Its optimized particle characteristics guarantee process stability in SLM. The classic NiCrMo chemistry delivers high strength, exceptional corrosion resistance, and outstanding biocompatibility, making it a standard material for permanent dental restorations. Its high hardness and stiffness are particularly advantageous for dental frameworks and clasps that must withstand significant mechanical stress over decades in the oral cavity.
4. SLM Process Parameter Recommendations
For SLM fabrication using NiCr powder, a recommended processing window includes laser power of 180–300 W, scanning speed of 800–1200 mm/s, layer thickness of 20–40 μm, and hatch spacing of 80–110 μm. Substrate preheating to 80–150°C is often used to reduce residual stress. High-purity argon protection must be maintained throughout the process, keeping chamber oxygen levels below 100 ppm. A stripe or chessboard scanning strategy with interlayer rotation is advised to homogenize heat accumulation. Post-printing stress relief annealing is typically required.
5. Post-Processing Procedures
Post-processing of NiCr printed parts begins with stress relief annealing at 700–900°C under vacuum or inert atmosphere to eliminate residual stresses. For critical dental frameworks, hot isostatic pressing (HIP) may be used to close any internal micropores and maximize fatigue life. Subsequent surface treatments include machining, grinding, and polishing to achieve the final dimensions and smooth surface finish required for dental applications. Throughout the process, atmospheric purity must be controlled to prevent surface oxidation.
6. Performance Specifications
In the as-built or heat-treated condition, NiCr alloy demonstrates high tensile strength (≥800 MPa), yield strength (≥500 MPa), good elongation (≥10%), a Young’s modulus of ~150 GPa, and Vickers hardness (≥300 HV). Its exceptional corrosion resistance in simulated oral fluid and proven biocompatibility ensure long-term reliability and functionality in complex physiological environments, meeting relevant international standards for dental alloys.
7. Application Areas
NiCr powder is primarily applied in dentistry for the direct SLM fabrication of customized, high-strength frameworks for porcelain-fused-to-metal (PFM) crowns, bridges, and removable partial dentures. It is also used for clasps and other non-aesthetic, high-strength dental components. Leveraging its excellent corrosion resistance, mechanical strength, and biocompatibility, it is a key material in the additive manufacturing of high-end, long-life dental prosthetics.
8. Comparison with Similar Powders
Compared to CoCr02 (CoCrMo), NiCr offers a lower cost alternative with slightly higher ductility but contains nickel, which can be a sensitizer for some patients. Versus pure titanium or Ti6Al4V, NiCr offers higher strength and stiffness, making it suitable for frameworks requiring minimal flex, though its biocompatibility profile is not as universally accepted as titanium for all patients. Compared to gold-based alloys, NiCr provides a much more cost-effective solution with comparable mechanical properties for many dental applications.
9. Precautions
NiCr powder contains nickel, which is a known sensitizer; full personal protective equipment (PPE) must be worn during handling, and operations should be conducted within closed systems—open exposure is strictly prohibited. Powder must be stored in a dry, inert environment. Before reuse, sieving and testing for property changes are mandatory. Waste powder must be disposed of as hazardous waste per regulations. Mixing powders from different batches is strictly forbidden.
10. Summary
NiCr Alloy Powder is a high-performance, dental-grade nickel-based alloy powder optimized for SLM additive manufacturing. Its well-established chemistry, excellent powder characteristics, and reliable process adaptability give it a leading position in dental prosthetic applications. This material delivers a powerful combination of high strength, exceptional corrosion resistance, and proven long-term biocompatibility, making it an indispensable material for manufacturing permanent, high-strength dental devices that demand precision, safety, and performance.
11. Customization Services by Forgecise
Forgecise delivers comprehensive dental CoCr alloy powder customization solutions, spanning the complete spectrum from standard biocompatible formulations to customer-specific high-performance cobalt-chromium alloys. We support mainstream dental alloy grades including CoCr01 (CoCrMoW), CoCrMo, and low-carbon variants, with the capability to precisely tailor chemical composition, particle size distribution, sphericity, oxygen/nitrogen content, and thermal expansion coefficient to match your exact clinical and manufacturing requirements. Our dental CoCr alloy powders are optimized for demanding additive manufacturing processes including SLM, EBM, ensuring consistent printability, high density, superior mechanical properties, and reliable metal-ceramic bonding performance in your final dental restorations and orthopedic components.
