Material Description

Polyoxymethylene (POM), also commonly known as Acetal, is a high-performance engineering thermoplastic with a distinctive combination of material properties that make it well-suited for a wide range of industrial applications. POM is characterized by its excellent mechanical strength and stiffness, which contribute to its outstanding dimensional stability and resistance to creep, even under heavy loads and elevated temperatures. This thermoplastic exhibits low friction and wear properties, making it an ideal choice for applications involving moving parts and gears, where it can significantly reduce frictional losses. POM also boasts good resistance to moisture, chemicals, and hydrolysis, making it suitable for use in demanding environments. Its low coefficient of linear expansion and excellent machinability enable precise component fabrication. Furthermore, POM is available in both homopolymer and copolymer variations, with the latter offering improved chemical resistance. Overall, Polyoxymethylene’s outstanding combination of mechanical, thermal, and chemical properties makes it a versatile choice for applications such as automotive components, gears, bearings, medical devices, and consumer goods.

Tensile Yield
Modulus (MPa)
Point (°C)
Coefficient of
(x 10^-6 /°C)
Absorption (%)
1370 - 144060 - 752.6 - 3.6160-1750.25 - 0.641.5 - 1.680 - 1100.2 - 0.7

Design Recommendation

When designing for injection molding of Polyoxymethylene (POM or Acetal), it is essential to focus on several key considerations to ensure the production of high-quality parts. First and foremost, it is crucial to pay careful attention to wall thickness uniformity to prevent issues such as warping, sink marks, and voids. Maintaining a consistent wall thickness in the design helps ensure proper material flow during the injection molding process. Additionally, undercuts and sharp corners should be minimized or avoided, as they can lead to challenges during demolding. Furthermore, draft angles should be incorporated into the design to facilitate easy part ejection from the mold. Material selection is also vital, as variations in POM grades can impact mechanical properties and overall performance. Finally, incorporating fillets and radii at the junctions of walls and ribs can enhance part strength and reduce stress concentrations. Careful attention to these design recommendations can result in successful POM injection molding with improved part quality and production efficiency.

Cost Saving Tip

Cost-saving in Polyoxymethylene (POM) or Acetal injection molding processes can be achieved through a combination of material selection, design optimization, and process efficiency improvements. Firstly, material selection is critical; opting for high-quality, filled grades of POM can reduce the need for excessive material usage while maintaining mechanical properties. Furthermore, optimizing part design for manufacturability by minimizing complex geometries and using uniform wall thicknesses can significantly reduce both material waste and cycle time. Implementing automated injection molding techniques and robotics for parts removal can enhance overall process efficiency. Additionally, employing mold temperature control systems and process monitoring equipment can help fine-tune operating parameters, leading to reduced energy consumption and minimized scrap rates. Regular equipment maintenance and implementing a comprehensive quality control system ensure consistent, high-quality output, ultimately reducing costly rework and material wastage. By adopting these strategies, manufacturers can effectively reduce costs in POM injection molding without compromising product quality or performance.