{"id":4196,"date":"2026-04-23T09:37:31","date_gmt":"2026-04-23T09:37:31","guid":{"rendered":"https:\/\/nylonplastic.com\/?p=4196"},"modified":"2026-06-10T06:03:39","modified_gmt":"2026-06-10T06:03:39","slug":"nylon-vs-pom-acetal-engineering-plastics-comparison","status":"publish","type":"post","link":"https:\/\/nylonplastic.com\/fr\/nylon-vs-pom-acetal-engineering-plastics-comparison\/","title":{"rendered":"Nylon vs. POM (ac\u00e9tal) : Guide de comparaison des plastiques techniques"},"content":{"rendered":"

Head-to-head comparison of nylon and POM (acetal\/delrin) for engineering applications \u2014 mechanical, thermal, chemical, wear, and processing differences.<\/p>\n

\"Nylon<\/p>\n

Nylon vs. POM: Two Giants of Engineering Plastics<\/h2>\n

\"Nylon<\/p>\n

Nylon (polyamide) and POM (polyoxymethylene, also called acetal or Delrin) are the two most-used engineering thermoplastics for mechanical components. Both offer excellent wear resistance, low friction, and good dimensional stability \u2014 but their different molecular structures create distinct performance trade-offs that matter enormously in precision applications.<\/p>\n

Choosing between nylon and POM is not trivial. A bearing that lasts 50,000 cycles in POM may fail in 8,000 cycles in nylon under the same load. Conversely, a gear housing exposed to automotive fluids will crack with POM but survive with PA66. This guide provides the data-driven comparison engineers need to make the right choice.<\/p>\n

Mechanical Properties Comparison<\/h2>\n\n\n\n\n\n\n\n
R\u00e9sistance \u00e0 la traction (MPa)<\/th>\n80<\/th>\n82<\/th>\n70<\/th>\n62<\/th>\n<\/tr>\n<\/thead>\n
Tensile Modulus (GPa)<\/td>\n2.8<\/td>\n3.0<\/td>\n2.8<\/td>\n2.5<\/td>\n<\/tr>\n
Flexural Strength (MPa)<\/td>\n100<\/td>\n110<\/td>\n98<\/td>\n90<\/td>\n<\/tr>\n
Module de flexion (GPa)<\/td>\n2.6<\/td>\n2.8<\/td>\n2.6<\/td>\n2.3<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n\n\n\n\n\n
Allongement \u00e0 la rupture (%)<\/th>\n150<\/th>\n60<\/th>\n40<\/th>\n35<\/th>\n<\/tr>\n<\/thead>\n
Creep Modulus (1000h, 20 MPa)<\/td>\n1.2 GPa<\/td>\n1.4 GPa<\/td>\n2.3 GPa<\/td>\n2.0 GPa<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

**Key Insight: Creep Resistance** \u2014 POM has significantly better creep resistance than nylon. Under sustained loading, POM retains more of its stiffness over time. For components under constant load (spring clips, retaining rings, fastener bushings), POM’s superior creep resistance often makes it the better choice despite similar initial strength.<\/p>\n

**Impact Resistance** \u2014 Nylon has higher unnotched impact resistance. But POM often outperforms nylon in notched impact tests because POM’s ductile failure mode absorbs more energy at the crack tip. For parts with stress concentrations (keyways, holes, threads), POM’s toughness at sharp notches is an advantage.<\/p>\n

**Fatigue Resistance** \u2014 Nylon has superior fatigue resistance for repeated loading. In cyclic loading tests, nylon components survive 3-5\u00d7 more cycles before failure than equivalent POM parts. Critical for components like conveyor belt guides, pump impellers, and hinge mechanisms.<\/p>\n

Thermal and Environmental Performance<\/h2>\n\n\n\n\n\n
Melting Point (\u00b0C)<\/th>\n225<\/th>\n265<\/th>\n175<\/th>\n<\/tr>\n<\/thead>\n
Continuous Service Temp (\u00b0C)<\/td>\n100-115<\/td>\n130-150<\/td>\n90-100<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n\n\n\n\n\n
HDT @ 1.82 MPa (\u00b0C)<\/th>\n65<\/th>\n90<\/th>\n95<\/th>\n<\/tr>\n<\/thead>\n
Thermal Expansion (\u00d710\u207b\u2075\/\u00b0C)<\/td>\n8-9<\/td>\n8-9<\/td>\n11-12<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

**POM’s thermal weakness** \u2014 The 175\u00b0C melting point of POM is its thermal limitation. At temperatures above 100\u00b0C, POM loses mechanical strength rapidly. PA66-GF30 (HDT 250\u00b0C) operates at temperatures where POM would melt.<\/p>\n\n\n\n\n\n
-<\/th>\n-<\/th>\n-<\/th>\n-<\/th>\n<\/tr>\n<\/thead>\n
Dimensional Change (saturation)<\/td>\n1.5-2.0%<\/td>\n1.3-1.8%<\/td>\n0.2%<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

**POM wins decisively on moisture** \u2014 At 0.8% maximum moisture absorption, POM is essentially dimensionally stable in humid environments. Nylon’s 8-9% absorption causes measurable swelling and property changes. For underwater or outdoor exposed applications without encapsulation, POM is often the only viable choice.<\/p>\n

Chemical Resistance: Where Each Material Excels<\/h2>\n\n\n\n\n\n\n\n\n\n\n
Gasoline\/Fuels<\/th>\nExcellent<\/th>\nExcellent<\/th>\n<\/tr>\n<\/thead>\n
Motor Oil<\/td>\nExcellent<\/td>\nExcellent<\/td>\n<\/tr>\n
Brake Fluid<\/td>\nBon<\/td>\nPoor (swells)<\/td>\n<\/tr>\n
Alcohol<\/td>\nExcellent<\/td>\nBon<\/td>\n<\/tr>\n
Ketones (Acetone)<\/td>\nBon<\/td>\nPoor (dissolves)<\/td>\n<\/tr>\n
Weak Acids<\/td>\nJuste<\/td>\nBon<\/td>\n<\/tr>\n
Strong Acids<\/td>\nPauvre<\/td>\nPauvre<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n\n\n\n\n\n
Esters\/Plasticizers<\/th>\nExcellent<\/th>\nPauvre<\/th>\n<\/tr>\n<\/thead>\n
Steam<\/td>\nPauvre<\/td>\nPauvre<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

**Critical Decision Points**:
\n– **Brake fluid or glycol coolants**: POM swells and cracks \u2014 use PA66 or PA12
\n– **Hot water (>60\u00b0C)**: Nylon hydrolyzes \u2014 use POM or PVDF
\n– **Plasticizer migration** (flexible cables, wire insulation): POM absorbs plasticizers \u2014 use PA12
\n– **Automotive under-hood**: PA66-GF30 for its heat resistance (180\u00b0C+) and fluid resistance
\n– **Consumer appliances**: POM for its dimensional stability and surface finish<\/p>\n

Wear and Friction Performance<\/h2>\n

Both materials offer low friction and good wear resistance \u2014 but with important differences:<\/p>\n\n\n\n
Coefficient of Friction (vs. steel, dry)<\/th>\n0.25-0.40<\/th>\n0.20-0.35<\/th>\n0.15-0.35<\/th>\n<\/tr>\n<\/thead>\n<\/table>\n\n\n\n\n\n
PV Limit (MPa\u00b7m\/min)<\/th>\n80-120<\/th>\n90-130<\/th>\n80-100<\/th>\n<\/tr>\n<\/thead>\n
Machinability<\/td>\nBon<\/td>\nExcellent<\/td>\nExcellent<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

**The critical difference: wear factor** \u2014 POM’s wear factor (1-3) is 10-20\u00d7 lower than nylon’s (10-40). This means POM parts generate less heat and wear more slowly in sliding contact. For high-PV applications (bearings, wear strips, sliding inserts), POM is the superior choice.<\/p>\n

**Self-lubricating versions**:
\n– **POM + PTFE**: Wear factor drops to 0.5-1.0 \u2014 excellent for boundary lubrication
\n– **PA6\/66 + PTFE or silicone**: Significantly reduces friction, but PTFE can migrate to surface and affect bonding
\n– **Carbon fiber reinforced**: Improves wear resistance in both materials, especially at elevated temperatures<\/p>\n

**Surface Speed Consideration**: At surface speeds above 1 m\/s in dry sliding, both materials generate enough heat to cause thermal softening. For high-speed applications, consider internally lubricated grades or oil-impregnated sintered bronze backings.<\/p>\n

How to Choose: Decision Framework<\/h2>\n

**Choose Nylon (PA66-GF30) when:**
\n– Operating temperature exceeds 100\u00b0C
\n– Repeated impact or cyclic loading is expected
\n– Exposure to brake fluid, coolants, or plasticizers
\n– You need higher fatigue life in dynamic loading
\n– Cost is the primary driver (PA66 is generally less expensive than POM)<\/p>\n

**Choose POM when:**
\n– Dimensional stability in humid environments is critical
\n– Low friction and low wear factor are priorities (sliding\/rotating contact)
\n– Parts will be exposed to hot water or steam
\n– Acetone, esters, or plasticizers are present
\n– You need excellent surface finish and tight tolerances<\/p>\n

**Hybrid Solution \u2014 Metal Replacement**:
\nFor many metal-replacement applications, the choice is not between nylon and POM, but between them and aluminum. Nylon-GF and POM are both excellent metal substitutes for housings, brackets, and structural components, offering 70-85% weight reduction vs. aluminum with adequate strength. For these applications, PA66-GF30 is the default choice due to its superior thermal and fluid resistance.<\/p>\n

\n

FAQ<\/h2>\n
\"Nylon
Nylon vs. POM (ac\u00e9tal) : Guide de comparaison des plastiques techniques<\/figcaption><\/figure>\n
\nWhen is Nylon vs. POM (Acetal): Engineering Plastics Comparison Guide a good option?<\/summary>\n
\n

Nylon vs. POM (Acetal): Engineering Plastics Comparison Guide is a good option when fast iteration, complex geometry, low tooling cost, or low-volume production is more important than molded-part unit cost.<\/p>\n<\/div>\n<\/details>\n

\nWhat should be checked before choosing Nylon vs. POM (Acetal): Engineering Plastics Comparison Guide?<\/summary>\n
\n

V\u00e9rifier la taille de la pi\u00e8ce, les propri\u00e9t\u00e9s du mat\u00e9riau, l'\u00e9tat de surface, la tol\u00e9rance dimensionnelle, l'exposition \u00e0 la chaleur, la direction de la charge et la n\u00e9cessit\u00e9 d'un post-traitement.<\/p>\n<\/div>\n<\/details>\n

\nHow does Nylon vs. POM (Acetal): Engineering Plastics Comparison Guide compare with CNC machining?<\/summary>\n
\n

L'impression 3D permet de cr\u00e9er rapidement des formes complexes, tandis que l'usinage CNC est souvent plus performant pour les surfaces pr\u00e9cises, les tol\u00e9rances plus \u00e9troites et les mat\u00e9riaux de qualit\u00e9.<\/p>\n<\/div>\n<\/details>\n

\nWhat affects the cost of Nylon vs. POM (Acetal): Engineering Plastics Comparison Guide?<\/summary>\n
\n

Le co\u00fbt d\u00e9pend du mat\u00e9riau, du volume de construction, du temps d'impression, de la hauteur des couches, de l'enl\u00e8vement du support, de la finition, de l'inspection et du nombre de pi\u00e8ces dans la construction.<\/p>\n<\/div>\n<\/details>\n<\/div>\n\t\t\t

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