Material Guide: ABS vs. PC vs. POM for Injection Molded Parts
Published 2026-08-02
ABS, polycarbonate and POM cover most injection molding programs we run. Choosing between them early avoids costly requalification later.
ABS — the dependable generalist
Good impact strength, easy to mold, takes paint and plating exceptionally well, and among the cheapest engineering resins. Dimensional stability is adequate but not stellar, and heat resistance tops out around 85–95 °C.
Choose ABS for: housings, interior automotive trim, painted cosmetic parts, prototypes.
PC — strength and transparency
Polycarbonate brings ~10× the impact strength of ABS, useful transparency, heat resistance to 125–135 °C and better dimensional stability. The trade-offs: higher material cost, a tendency toward stress cracking around sharp features (design generous radii), and it requires thorough drying before molding to avoid splay.
Choose PC for: safety components, optical and transparent parts, medical device housings, outdoor equipment.
POM (Acetal / Delrin) — the precision workhorse
POM offers low friction, high stiffness, excellent fatigue resistance and superb dimensional stability. It machines and molds cleanly with tight tolerances. Weaknesses: poor adhesion for painting, limited color choice, and it degrades if held at melt temperature too long.
Choose POM for: gears, sliding mechanisms, precision clips, fluid-handling components.
Quick comparison
| Property | ABS | PC | POM | |---|---|---|---| | Impact strength | Good | Excellent | Moderate | | Heat resistance (°C) | 85–95 | 125–135 | 90–110 | | Cost | Low | Medium | Medium | | Paintability | Excellent | Good | Poor | | Dimensional stability | Fair | Good | Excellent | | Typical tolerance | ±0.1 mm | ±0.08 mm | ±0.05 mm |
Two hybrids to know
PC/ABS blends PC's toughness with ABS's moldability and finish — the default for consumer electronics enclosures. Glass-filled PA6/PA66 (10–50% GF) replaces metal in structural brackets; expect warpage management and fiber-orientation analysis from a competent molder.
Unsure which resin fits your loads, temperatures and certifications? Send us the part — we'll propose two or three candidate materials with cost and performance trade-offs.