Dans 3Impression D, pourquoi un jouet en PLA et une pièce automobile en ABS ont-ils des durées de vie radicalement différentes? The answer lies in the hardness of material for 3D printing—a key property that determines a part’s ability to resist scratches, déformation, et porter. Le choix d'un matériau avec une dureté incorrecte peut entraîner une défaillance prématurée d'une pièce., whether it’s a brittle PLA prototype or an over-hardened metal component that cracks under stress. This article breaks down the hardness characteristics of common 3D printing materials, how to measure hardness, applications du monde réel, and selection tips, helping you match material hardness to your project’s needs.
What Is Hardness in 3D Printing Materials?
Hardness of material for 3D printing refers to a material’s ability to resist permanent deformation (like dents or scratches) when exposed to external pressure or force. It directly impacts three critical part performance factors:
- Résistance à l'usure: Harder materials (par ex., acier inoxydable) resist wear from friction, making them ideal for moving parts like gears.
- Résistance aux chocs: Balanced hardness (not too hard, not too soft) helps parts absorb impacts—for example, ABS’s moderate hardness prevents it from shattering like brittle PLA.
- Service Life: Materials with appropriate hardness last longer in their intended use—stainless steel medical implants (high hardness) outlast PLA prototypes by years.
Think of hardness as a “protective shield”: a harder shield (par ex., alliage de titane) defends against scratches and pressure, while a softer shield (par ex., PLA) is more flexible but less durable.
How to Measure the Hardness of 3D Printing Materials
Hardness isn’t a one-size-fits-all metric—different materials use different testing methods. Below are the three most common measurement standards, along with how they apply to 3D printing materials:
| Méthode de mesure | Comment ça marche | Ideal for Materials | Example Values for Common 3D Materials |
| Dureté Shore (A/D) | Uses a durometer to measure indentation depth under a fixed load; Shore A for soft materials, Shore D for hard plastics. | Plastiques (PLA, ABS, PETG) | – PLA: Shore D 50–60 – ABS: Shore D 70–80 – PETG: Shore D 65–75 |
| Rockwell Hardness (CRH) | Measures the depth of indentation from a diamond or steel ball under two loads; focuses on metal hardness. | Métaux (acier inoxydable, alliage de titane) | – Acier inoxydable: HRC 25–30 – Alliage de titane: HRC 30–35 |
| Vickers Hardness (HT) | Uses a diamond pyramid indenter to create a square indentation; calculates hardness from indentation size. | Matériaux composites (carbon fiber reinforced nylon) et métaux | – Carbon Fiber Reinforced Nylon: HV 120–150 – Alliage de titane: HV 300–350 |
Hardness Characteristics of Common 3D Printing Materials
Not all 3D printing materials have the same hardness—each is engineered for specific uses. The table below details the hardness, propriétés clés, and ideal applications of 6 popular materials:
| Type de matériau | Dureté (Common Measurement) | Key Properties Related to Hardness | Applications idéales |
| PLA (Acide polylactique) | Shore D 50–60 | – Lowest hardness among common plastics – Fragile (breaks under high impact) – Biodégradable, odorless | – Prototypes (par ex., toy models, display props) – Indoor decorative parts (par ex., pots de fleurs) – Non-functional parts (par ex., 3D printed art) |
| ABS (Acrylonitrile-Butadiène-Styrène) | Shore D 70–80 | – Moderate hardness – Haute ténacité (resists impact without breaking) – Bonne stabilité dimensionnelle | – Pièces automobiles (par ex., garniture intérieure, dashboard brackets) – Home appliance shells (par ex., small fan casings) – Prototypes fonctionnels (par ex., poignées d'outils) |
| PETG (Polyethylene Terephthalate Copolymer) | Shore D 65–75 | – Balanced hardness (between PLA and ABS) – Haute résistance aux chocs – Résistant aux produits chimiques (résiste aux huiles/solvants) | – Food-contact parts (par ex., clear containers) – Outdoor small parts (par ex., garden light covers) – Composants structurels (par ex., cadres de drones) |
| Acier inoxydable | HRC 25–30 / HV 200–250 | – Haute dureté – Excellente résistance à la corrosion – Haute résistance (supports heavy loads) | – Composants aérospatiaux (par ex., small engine parts) – Dispositifs médicaux (par ex., surgical instrument tips) – Outils industriels (par ex., wear-resistant nozzles) |
| Alliage de titane | HRC 30–35 / HV 300–350 | – Ultra-high hardness – Léger (1/2 le poids de l'acier) – Biocompatible (sans danger pour l'implantation humaine) | – Implants médicaux (par ex., artificial hip joints, couronnes dentaires) – Pièces aérospatiales (par ex., aircraft wing brackets) – High-performance sports equipment (par ex., cadres de vélo) |
| Carbon Fiber Reinforced Nylon | HV 120–150 / Shore D 80–85 | – Haute dureté (harder than most plastics) – Rapport résistance/poids élevé – Resists warping | – Pièces de structure automobile (par ex., composants de suspension) – Sports gear (par ex., tennis racket frames) – Pièces de machines industrielles (par ex., roues dentées) |
Real-World Cases: Matching Hardness to Application
Choosing the right hardness avoids costly mistakes. Voici 3 practical cases showing how hardness impacts part performance:
1. Cas 1: PLA for Indoor Prototypes
- Problème: A designer needs a 3D printed prototype of a new phone case to test fit. Using a hard material like ABS would be overkill and more expensive.
- Solution: PLA (Shore D 50–60) is soft enough to print quickly and cheaply, yet rigid enough to show the phone case’s shape. The prototype works for fit testing and costs 50% less than an ABS version.
- Résultat: The designer iterates 3 times on the PLA prototype before finalizing the design, saving time and material costs.
2. Cas 2: Stainless Steel for Medical Tools
- Problème: A medical device firm needs 3D printed surgical instrument tips that resist wear from repeated use and sterilization. Soft plastics like PETG would scratch and degrade quickly.
- Solution: Acier inoxydable (HRC 25–30) has high hardness and corrosion resistance. The instrument tips withstand 100+ autoclave sterilization cycles and show no visible wear after 6 months of use.
- Impact: The firm reduces tool replacement costs by 70% compared to plastic instruments.
3. Cas 3: Carbon Fiber Reinforced Nylon for Drone Frames
- Problème: A drone maker uses ABS for frames, but the frames crack under hard landings—ABS’s moderate hardness isn’t enough for the impact.
- Solution: Switch to carbon fiber reinforced nylon (HV 120–150). Its higher hardness and toughness absorb impact energy, and the frames survive 10+ hard landings (contre. 2–3 for ABS).
- Résultat: The drone’s failure rate drops from 15% à 2%, improving customer satisfaction.
How to Choose the Right Hardness for Your 3D Printing Project
Follow this 4-step process to match material hardness to your needs:
- Define Your Part’s Purpose:
- Demander: Will the part be functional (par ex., un engrenage) ou décoratif (par ex., une figurine)? Functional parts need higher hardness; decorative parts can use softer materials.
- Identify Environmental Stressors:
- List forces the part will face: friction (needs high hardness), impact (needs balanced hardness), or corrosion (needs hard, corrosion-resistant materials like stainless steel).
- Check Hardness Data:
- Use the table in the previous section to narrow down materials. Par exemple:
- Indoor prototype → PLA (Shore D 50–60).
- Medical implant → Titanium alloy (HRC 30–35).
- Test with Small Samples:
- Print a small test piece (par ex., a 2cm×2cm cube) of your chosen material. Test its hardness with a durometer (pour les plastiques) or hardness tester (pour les métaux) to confirm it meets your needs.
Yigu Technology’s Perspective
Chez Yigu Technologie, we see the hardness of material for 3D printing as a critical yet often overlooked factor in part performance. Our 3D printers are optimized to enhance material hardness: our FDM printers (YG-FDM 800) use precise temperature control to boost ABS’s Shore D hardness by 5–10%, while our metal 3D printers (YG-Metal 500) ensure stainless steel parts reach HRC 30 for maximum wear resistance. We also provide free hardness testing for clients, helping them confirm material suitability before full production. As new materials emerge (par ex., ultra-hard ceramic composites), we’ll keep updating our systems to unlock their full hardness potential.
FAQ
- Q: Can I increase the hardness of a 3D printed part after printing?
UN: Oui! Pour les plastiques: Post-cure resin parts with UV light (boosts Shore D hardness by 5–10%); coat PLA/ABS parts with epoxy (adds a hard, scratch-resistant layer). For metals: Heat-treat stainless steel parts (annealing at 800°C increases HRC by 3–5).
- Q: Is a harder material always better for 3D printing?
UN: Non. Overly hard materials (par ex., titanium alloy for a simple prototype) are more expensive and harder to print. Matériaux souples (par ex., PLA for decorative parts) are cheaper and more flexible—choose based on your part’s use, not just hardness.
- Q: How do I measure the hardness of my 3D printed part at home?
UN: Pour les plastiques: Use a handheld Shore D durometer (frais \(50–)100) — press it against the part’s flat surface and read the value. For metals: You’ll need a professional Rockwell tester (often available at local engineering labs for a small fee).