Polystyrene (PS) is a versatile and cost-effective thermoplastic widely used for prototyping, modeling, and specific end-use parts. Known for its excellent clarity, rigidity, and ease of fabrication, PS is a popular choice for CNC machining. It machines easily to create parts with smooth surfaces and tight tolerances, making it ideal for a wide range of applications where high performance engineering plastics are not required. While it has limitations in impact strength and chemical resistance, its low cost and manufacturability make it an excellent solution for visual and low-stress functional components.
KEY BENEFITS
This table outlines the primary advantages and limitations of CNC machining Polystyrene to help guide your material selection.
| Key Benefits | Key Considerations |
|---|---|
| Excellent Machinability: PS machines easily with minimal tool wear, allowing for high-speed machining and excellent surface finishes. | Brittleness: PS is a relatively brittle plastic with low impact strength, making it unsuitable for parts subject to shock or high stress. |
| High Clarity & Gloss: General Purpose PS (GPPS) offers crystal-clear transparency, perfect for lenses, light pipes, and display models. | Poor Chemical Resistance: It is susceptible to many chemicals, including oils, greases, and hydrocarbons, which can cause stress cracking. |
| Cost-Effective: One of the most economical engineering plastics available, reducing overall part cost. | Low UV Resistance: Unmodified PS can yellow and degrade when exposed to prolonged sunlight without stabilizers. |
| Stiffness & Dimensional Stability: PS provides good rigidity and maintains its shape well under light loads. | |
| Lightweight: Its low density makes it ideal for applications where weight is a concern. |
APPLICATIONS
CNC Machined Polystyrene is suitable for a diverse range of applications across various industries. The following table provides specific examples.
| Industry / Field | Specific Part Examples |
|---|---|
| Prototyping & Models | Concept models, fit-and-function prototypes, architectural models, presentation models. |
| Consumer Electronics | Translight panels, button prototypes, housing mock-ups, lens prototypes for displays. |
| Automotive | Interior trim prototypes, light reflector housings, concept model components. |
| Packaging | Custom clamshell packaging prototypes, high-end display trays and inserts. |
| Medical & Lab | Disposable labware prototypes (petri dishes, test tube racks), diagnostic device housings. |
| Advertising & Display | Point-of-sale (POS) displays, lettering, signage, and decorative elements. |
TECHNICAL SPECIFICATIONS
The following table summarizes the key technical properties of Polystyrene for engineering and design reference.
| Property | Value / Description | Test Method |
|---|---|---|
| Density | 1.04 – 1.05 g/cm³ | ASTM D792 |
| Tensile Strength | 40 – 60 MPa | ASTM D638 |
| Flexural Modulus | 3,000 – 3,500 MPa | ASTM D790 |
| Impact Strength (Izod Notched) | 20 – 25 J/m | ASTM D256 |
| Heat Deflection Temp (HDT) @ 1.82 MPa | 85 – 95 °C | ASTM D648 |
| Melting Point | ~ 240 °C | – |
| Dielectric Strength | 19 – 22 kV/mm | ASTM D149 |
| Water Absorption (24hr) | 0.1 – 0.3% | ASTM D570 |
| Shrink Rate | 0.4 – 0.7% | – |
| Rockwell Hardness | M65 – M80 | ASTM D785 |