Em 3Impressão D, why do a PLA toy and an ABS automotive part have drastically different lifespans? The answer lies in the hardness of material for 3D printing—a key property that determines a part’s ability to resist scratches, deformação, e desgaste. Choosing a material with the wrong hardness can lead to premature part failure, 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, aplicações do mundo real, 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:
- Resistência ao desgaste: Harder materials (por exemplo, aço inoxidável) resist wear from friction, making them ideal for moving parts like gears.
- Resistência ao Impacto: 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 (por exemplo, liga de titânio) defends against scratches and pressure, while a softer shield (por exemplo, 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:
| Método de medição | Como funciona | Ideal for Materials | Example Values for Common 3D Materials |
| Dureza Shore (A/D) | Uses a durometer to measure indentation depth under a fixed load; Shore A for soft materials, Shore D for hard plastics. | Plásticos (PLA, ABS, PETG) | – PLA: Shore D 50–60 – ABS: Shore D 70–80 – PETG: Shore D 65–75 |
| Rockwell Hardness (CDH) | Measures the depth of indentation from a diamond or steel ball under two loads; focuses on metal hardness. | Metais (aço inoxidável, liga de titânio) | – Aço inoxidável: HRC 25–30 – Liga de titânio: HRC 30–35 |
| Vickers Hardness (Alta tensão) | Uses a diamond pyramid indenter to create a square indentation; calculates hardness from indentation size. | Materiais compósitos (carbon fiber reinforced nylon) e metais | – Carbon Fiber Reinforced Nylon: HV 120–150 – Liga de titânio: 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, propriedades principais, and ideal applications of 6 popular materials:
| Tipo de material | Dureza (Common Measurement) | Key Properties Related to Hardness | Aplicações ideais |
| PLA (Ácido Polilático) | Shore D 50–60 | – Lowest hardness among common plastics – Frágil (breaks under high impact) – Biodegradável, odorless | – Protótipos (por exemplo, toy models, display props) – Indoor decorative parts (por exemplo, vasos de plantas) – Non-functional parts (por exemplo, 3D printed art) |
| ABS (Acrilonitrila-Butadieno-Estireno) | Shore D 70–80 | – Moderate hardness – Alta tenacidade (resists impact without breaking) – Boa estabilidade dimensional | – Peças automotivas (por exemplo, acabamento interno, dashboard brackets) – Home appliance shells (por exemplo, small fan casings) – Protótipos funcionais (por exemplo, cabos de ferramentas) |
| PETG (Polyethylene Terephthalate Copolymer) | Shore D 65–75 | – Balanced hardness (between PLA and ABS) – Alta resistência ao impacto – Resistente a produtos químicos (resiste a óleos/solventes) | – Food-contact parts (por exemplo, clear containers) – Outdoor small parts (por exemplo, garden light covers) – Componentes estruturais (por exemplo, quadros de drones) |
| Aço inoxidável | HRC 25–30 / HV 200–250 | – Alta dureza – Excelente resistência à corrosão – Alta resistência (supports heavy loads) | – Componentes aeroespaciais (por exemplo, small engine parts) – Dispositivos médicos (por exemplo, surgical instrument tips) – Ferramentas industriais (por exemplo, wear-resistant nozzles) |
| Liga de titânio | HRC 30–35 / HV 300–350 | – Ultra-high hardness – Leve (1/2 o peso do aço) – Biocompatível (seguro para implantação humana) | – Implantes médicos (por exemplo, artificial hip joints, coroas dentárias) – Peças aeroespaciais (por exemplo, aircraft wing brackets) – High-performance sports equipment (por exemplo, quadros de bicicleta) |
| Carbon Fiber Reinforced Nylon | HV 120–150 / Shore D 80–85 | – Alta dureza (harder than most plastics) – Alta relação resistência-peso – Resists warping | – Peças estruturais automotivas (por exemplo, componentes de suspensão) – Sports gear (por exemplo, tennis racket frames) – Peças de máquinas industriais (por exemplo, rodas dentadas) |
Real-World Cases: Matching Hardness to Application
Choosing the right hardness avoids costly mistakes. Aqui estão 3 practical cases showing how hardness impacts part performance:
1. Caso 1: PLA for Indoor Prototypes
- Problema: 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.
- Solução: 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.
- Resultado: The designer iterates 3 times on the PLA prototype before finalizing the design, saving time and material costs.
2. Caso 2: Stainless Steel for Medical Tools
- Problema: 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.
- Solução: Aço inoxidável (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. Caso 3: Carbon Fiber Reinforced Nylon for Drone Frames
- Problema: A drone maker uses ABS for frames, but the frames crack under hard landings—ABS’s moderate hardness isn’t enough for the impact.
- Solução: Switch to carbon fiber reinforced nylon (HV 120–150). Its higher hardness and toughness absorb impact energy, and the frames survive 10+ hard landings (contra. 2–3 for ABS).
- Resultado: The drone’s failure rate drops from 15% para 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:
- Perguntar: Will the part be functional (por exemplo, uma engrenagem) ou decorativo (por exemplo, uma estatueta)? Functional parts need higher hardness; decorative parts can use softer materials.
- Identify Environmental Stressors:
- List forces the part will face: atrito (needs high hardness), impacto (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. Por exemplo:
- Indoor prototype → PLA (Shore D 50–60).
- Medical implant → Titanium alloy (HRC 30–35).
- Test with Small Samples:
- Print a small test piece (por exemplo, a 2cm×2cm cube) of your chosen material. Test its hardness with a durometer (para plásticos) or hardness tester (para metais) to confirm it meets your needs.
Yigu Technology’s Perspective
Na tecnologia Yigu, 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 (por exemplo, ultra-hard ceramic composites), we’ll keep updating our systems to unlock their full hardness potential.
Perguntas frequentes
- P: Can I increase the hardness of a 3D printed part after printing?
UM: Sim! Para plásticos: 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).
- P: Is a harder material always better for 3D printing?
UM: Não. Overly hard materials (por exemplo, titanium alloy for a simple prototype) are more expensive and harder to print. Materiais macios (por exemplo, PLA for decorative parts) are cheaper and more flexible—choose based on your part’s use, not just hardness.
- P: How do I measure the hardness of my 3D printed part at home?
UM: Para plásticos: Use a handheld Shore D durometer (custos \(50–\)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).