CNC Machining Bakelite
Material Description
Bakelite, also known as polyoxybenzylmethylenglycolanhydride, is a thermosetting plastic material with a rich history as one of the first synthetic plastics. It was developed by Belgian chemist Leo Baekeland in 1907 and quickly gained popularity for its remarkable electrical insulating properties and resistance to heat and chemicals. Bakelite is composed of phenol and formaldehyde, which are polymerized through a condensation reaction to form a three-dimensional network structure. This results in a rigid and highly cross-linked material that cannot be melted or reshaped once it is cured.
Technically, Bakelite is characterized by its exceptional electrical insulating properties, making it an ideal choice for electrical components and insulators. It can withstand high temperatures without softening or losing its shape, which is particularly advantageous for applications involving heat or electrical currents. Additionally, Bakelite is highly resistant to various chemicals, making it suitable for use in corrosive environments. Its durability, electrical insulating capabilities, and resistance to both heat and chemicals have led to its use in a wide range of applications, from electrical switches and handles for kitchenware to automotive parts and jewelry, making Bakelite a significant advancement in the history of materials science and engineering.
Grades
Phenolic Bakelite
Finishing Options
Molding with Color, Polishing
| Density | Tensile Yield Strength (MPa) | Fatigue Strength (MPa) | Hardness (Brinell) | Thermal Conductivity (W/m-K) | Coeff. of Thermal Expansion (mm/mdeg) | Electrical Resistivity (micro Ohm-cm) |
|---|---|---|---|---|---|---|
| 1250 | 140-800 | 40-80 | N/A (Not applicable) | - | 50-75 | 1x10^12 - 1x10^16 |
Design Recommendation
When designing with Bakelite, a thermosetting plastic renowned for its durability and electrical insulating properties, it’s crucial to prioritize molding techniques that account for its brittle nature. Employing smooth, rounded edges and avoiding sharp corners can reduce the risk of cracking during the molding process. Additionally, Bakelite tends to shrink upon cooling, so precise calculations for mold dimensions and clearances should be made to achieve the desired final shape. Furthermore, maintaining a consistent wall thickness and incorporating reinforcement structures, such as ribs, can enhance structural integrity. Careful consideration of heat and pressure parameters during molding is essential to ensure the material’s optimal properties are preserved, resulting in a reliable and resilient product.
Cost Saving Tip
Bakelite is a thermosetting plastic, and for cost-effective machining, it’s best to use HSS tools. Control feed rates to prevent excessive tool wear, while maintaining precision for high-quality results and overall cost-effectiveness.
