PCB Board FR-4, 2 copper planes vs. Plastic Nylon PA66

Compare PCB Board FR-4, 2 copper planes vs. Plastic Nylon PA66 strength, stiffness, weight and thermal properties.

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PCB Board FR-4, 2 copper planesComposite

Plastic Nylon PA66Bulk polymer (molded or machined)

Mechanical
Try it on a partA sample part to run stress or thermal on, free in your browser	Open in LessCAD	Open in LessCAD
Yield strength	not given (tensile used)	85MPasourcetypical, dry
Ultimate tensile strength	246–385MPasourcethe bare laminate's (fr4-370hr), in-plane: cross direction .. length direction (ASTM D3039)	not sourced
Elongation at break	not sourced	30%sourcenominal strain at break, dry
Young's modulus (stiffness)	21.9–25.8GPasourcethe bare laminate's (fr4-370hr), in-plane: cross direction .. length direction (ASTM D790-15e2); the copper planes are left out	3GPasourcetypical, dry
Density	not sourced	1,130kg/m³sourcetypical
Strength to weight	not sourced	75.2kN·m/kg
Stiffness to weight	not sourced	2.65MN·m/kg
Poisson's ratio	0.171–0.177sourcethe bare laminate's (fr4-370hr), in-plane: cross direction .. length direction	0.4sourcebase material: unfilled polyamide (PA), conditioned, maker design-guide family value (Covestro Table 3-1)
Shear modulus	10.2GPa9.48x stiffer in shear	1.07GPa
Bulk modulus	12.2GPa	5GPa
Speed of sound	not sourced	1,629m/s
Thermal
Thermal conductivity	not sourced	0.33W/m·Ksourcetypical
Thermal expansion	13–14µm/m·Ksourcethe bare laminate's (fr4-370hr), in-plane X/Y-axis, below Tg (IPC-TM-650 2.4.24C)	98µm/m·Ksourcelongitudinal, 23-55 °C
100 mm part over a 50 °C swing	67.5µm growth7.26x less	490µm growth
Specific heat	not sourced	1,700J/kg·Ksourcetypical
Heats up and cools (diffusivity)	not sourced	0.172mm²/s
Thermal shock resistance	not sourced	57.2W/m
Melting point	not sourced	260°CsourceDSC
Max service temperature	not sourced	101°CsourceIEC 60216 temperature index, 20000 h
Values for	A whole circuit board read as one orthotropic plate: the JEDEC high-K thermal test board (JESD51-7, "2s2p"), 0.062 in (1.575 mm) thick with two internal solid copper planes 0.0014 in (1 oz) thick, as Texas Instruments SZZA017A Table 1 gives it. Copper C110 and the Isola 370HR laminate from this library; the layers conduct in parallel along the board and in series through it (boardStackup.ts). Its two 0.0028 in trace layers cover little of the board and are left out; vias are ignored. Mechanical values are the bare laminate's.	BASF Ultramid A3K (PA66, unreinforced injection-moulding grade), Product Information 02/2026, dry values (ISO methods)

Every value links to the document that states it. "Not sourced" means no citable source states it (or only a specification minimum); figures computed from it are left out too.

Questions

Is PCB Board FR-4, 2 copper planes stronger than Plastic Nylon PA66?

PCB Board FR-4, 2 copper planes is stronger: its tensile strength is 315 MPa against yield strength 85 MPa for Plastic Nylon PA66 (3.71x).

Which is stiffer, PCB Board FR-4, 2 copper planes or Plastic Nylon PA66?

PCB Board FR-4, 2 copper planes is stiffer: Young's modulus 23.9 GPa against 3 GPa for Plastic Nylon PA66, so the same part in PCB Board FR-4, 2 copper planes deflects less under the same load.

Which expands less with temperature?

PCB Board FR-4, 2 copper planes expands less: 13.5 µm/m·K against 98 µm/m·K for Plastic Nylon PA66.

Among 73 materials

Stiffness against density

Strength against density