The most commonly used materials in dental micromotors are stainless steel and aluminum alloy. They play core roles in different components, balancing durability, sterilization requirements, and operational performance.
Stainless Steel: Primarily used for motor housings and internal bearing assemblies. Due to its excellent high-temperature resistance and corrosion resistance, it can withstand repeated high-pressure steam sterilization (e.g., 134°C, 2 bar), making it one of the most widely used materials in clinical environments. In particular, 440C martensitic stainless steel is widely used in high-end dental drill bearings, achieving high hardness (HRC58 and above) and grease-free operation.
Aluminum Alloy: Often used in lightweight housing designs, it offers advantages such as light weight, good heat dissipation, and ease of molding, making it suitable for high-speed handpiece devices requiring prolonged gripping. Although its mechanical strength is lower than stainless steel, surface oxidation treatment can improve wear resistance.
Engineering Plastics: Some low-speed motors or connecting parts use high-temperature resistant engineering plastics, which have good electrical insulation and anti-slip textured designs, facilitating grip by dentists while reducing overall cost.
In summary, stainless steel is the most frequently used material in critical structural components due to its excellent stability and biocompatibility, especially in parts that come into direct contact with the oral environment or require high-frequency sterilization.
