Low temperature motor

When using servo motors in low-temperature environments, material selection must carefully consider the effects of cold conditions on mechanical properties, lubrication performance, electrical insulation, and structural stability. Below are key material selection points and design recommendations: 1. Metal Structural Materials Housing and Bearings: Aluminum Alloy: Commonly used grades such as 6061 or 7075, subjected to T6 heat treatment to improve low-temperature toughness. Avoid ordinary cast iron (increased brittleness). Stainless Steel: Grades like 304 or 316 offer low-temperature resistance and corrosion protection, suitable for extreme environments. Bearing Steel: Use low-temperature-specific bearing steel (e.g., GCr15SiMn) or hybrid ceramic bearings (silicon nitride) to prevent reduced ductility in cold conditions. Shaft Materials: Maraging Steel (e.g., 18Ni300): High strength with excellent low-temperature toughness. Low-Temperature Nickel Steel (e.g., 9% Ni Steel): Alternative for enhanced performance. 2. Lubricants Low-Temperature Grease: Base Oil: Polyalphaolefin (PAO) or ester-based oils with lithium complex or polyurea thickeners. Recommended Products: Mobilgrease 28 (-40°C to 150°C) Klüber Isoflex Topas NB 52 (-60°C to 120°C) Solid Lubricants: For ultra-low temperatures (<-60°C), consider molybdenum disulfide (MoS₂) or graphite coatings. 3. Electrical Components Coil Insulation: Magnet Wire: Polyimide (e.g., Kapton) or PTFE-coated wires; avoid PVC (becomes brittle at low temperatures). Impregnation Resin: Modified epoxy or silicone resins (e.g., Dow Corning 1-2577). PCB Substrates: High-Tg materials (e.g., FR-4 Tg≥170°C) or polyimide flexible circuits. 4. Seals and Elastomers Seals: Nitrile Rubber (NBR): Suitable above -40°C. Fluorocarbon (FKM) or Silicone Rubber (e.g., modified EPDM): Required below -40°C. Damping Components: Polyurethane (PU) or specialty silicone, with validation of low-temperature elasticity. 5. Other Critical Materials Magnets: Neodymium (NdFeB) magnets exhibit improved magnetic properties at low temperatures but require plating (e.g., Ni-Cu-Ni). Samarium cobalt (SmCo) magnets for ultra-low temperatures. Thermal Interface Materials: Low-temperature thermal grease (e.g., Bergquist SIL-Pad 2000) for motor-heatsink interfaces. 6. Design Validation Material Testing: Conduct impact tests (e.g., Charpy), shrinkage rate, and insulation resistance measurements at target temperatures. Assembly Tolerances: Account for differential thermal contraction (e.g., aluminum vs. steel CTE ratio ~2:1) via gaps or compensation structures. Step Cooling Tests: Gradually reduce temperature while monitoring torque fluctuations, bearing resistance, etc. Targeted material selection and rigorous validation ensure servo motors maintain precision, reliability, and longevity in low-temperature conditions. Practical applications should further optimize based on specific operational factors (e.g., cold-start frequency, load type). Zhonggu Weike (Shenzhen) Power Technology Co., Ltd. is a National Specialized, Sophisticated, and Innovative ("Little Giant") enterprise specializing in the R&D, manufacturing, and application of special motors for harsh environments, including vacuum, high temperature, cryogenic, deep cryogenic, and radiation conditions. Its product range includes stepper motors, servo motors, radiation-resistant motors, vacuum modules, and vacuum gearboxes, among other standardized series.

In order to ensure the normal operation of stepper motors in different environments, corresponding design and maintenance measures need to be taken according to specific environmental conditions. The following are the factors to be considered in the material selection and design of low-temperature stepper motors: Material Selection Magnetic Materials: Select materials with stable magnetic properties at low temperatures, such as neodymium iron boron (NdFeB) permanent magnets. Insulating Materials: Choose insulating materials resistant to low temperatures, such as polyimide or polytetrafluoroethylene (PTFE). Structural Materials: Use materials with good mechanical properties at low temperatures, such as stainless steel or aluminum alloy. Lubrication Lubricants: Select lubricants that can still maintain their lubricating properties at low temperatures, such as perfluoropolyether (PFPE) or silicone-based lubricants. Thermal Management Thermal Expansion: Consider the thermal expansion coefficient of materials at low temperatures to avoid structural problems caused by shrinkage. Heating Elements: Add heating elements when necessary to ensure the normal startup and operation of the motor at low temperatures. Electrical Design Coil Design: Optimize the coil design to reduce the impact of resistance changes on performance at low temperatures. Driver Design: Select drivers suitable for low-temperature environments to ensure stable control. Mechanical Design Clearance and Tolerance: Consider the shrinkage of materials at low temperatures and appropriately adjust the mechanical clearance and tolerance. Bearing Design: Select bearings with stable performance at low temperatures, such as ceramic bearings. Testing and Verification Low-Temperature Testing: Conduct sufficient tests in a low-temperature environment to verify the performance of the motor. Environmental Sealing Sealing Design: Prevent condensed water or ice from entering the interior of the motor, which may affect its operation. Maintenance and Operation Maintenance Plan: Develop a maintenance plan for low-temperature environments to ensure the long-term stable operation of the motor. By comprehensively considering these factors, the reliability and performance of stepper motors in low-temperature environments can be ensured.