"FR" stands for FLAME RETARDANT, and denotes that safety of
flammability of
NEMA is the regulating authority for
CONTENTS * 1 Properties * 2 Applications * 2.1 Printed circuit boards * 2.1.1 Specifications * 2.2 Other applications * 3 See also * 4 References PROPERTIES
PARAMETER VALUE Speciﬁc gravity/density 1.850 g/cm3 (3,118 lb/cu yd) Water absorption −0.125 in < 0.10% Temperature index 140 °C (284 °F)
Thermal conductivity, in-plane 0.81 W/(m·K), 1.059 W/(m·K) Rockwell hardness 110 M scale Bond strength > 1,000 kg (2,200 lb) Flexural strength (A; 0.125 in) - LW > 415 MPa (60,200 psi) Flexural strength (A; 0.125 in) - CW > 345 MPa (50,000 psi) Dielectric breakdown (A) > 50 kV Dielectric breakdown (D48/50) > 50 kV
Dielectric constant permittivity 4.70 max., 4.35 @ 500 MHz, 4.34 @ 1 GHz Glass transition temperature Can vary, but is over 120 °C Young's modulus - LW 3.5×10^6 psi (24 GPa) Young's modulus - CW 3.0×10^6 psi (21 GPa) Coefficient of thermal expansion - x-axis 1.4×10−5 K−1 Coefficient of thermal expansion - y-axis 1.2×10−5 K−1 Coefficient of thermal expansion - z-axis 7.0×10−5 K−1 Poisson's ratio - LW 0.136 Poisson's ratio - CW 0.118 LW sound speed 3602 m/s SW sound speed 3369 m/s LW Acoustic impedance 6.64 MRayl where: LW = lengthwise CW = crosswise PF = perpendicular to laminate face APPLICATIONS PRINTED CIRCUIT BOARDS
Specifications When ordering a copper clad laminate board, the
In the USA,
In the USA, copper foil thickness is specified in units of ounces per square foot (oz/ft2), commonly referred to simply as ounce. Common thicknesses are 1 oz/ft2 (300 g/m2), 2 oz/ft2 (600 g/m2), and 3 oz/ft2 (900 g/m2). These work out to thicknesses of 34.1 µm (1.34 thou ), 68.2 µm (2.68 thou), and 102.3 µm (4.02 thou), respectively. Some PCB manufacturers refer to 1 oz/ft2 copper foil as having a thickness of 35 µm (may also be referred to as 35 μ, 35 micron , or 35 mic). * 1/0 - denotes 1 oz/ft2 copper one side, with no copper on the other side. * 1/1 - denotes 1 oz/ft2 copper on both sides. * H/0 or H/H - denotes 0.5 oz/ft2 copper on one or both sides, respectively. * 2/0 or 2/2 - denotes 2 oz/ft2 copper on one or both sides, respectively. OTHER APPLICATIONS
SEE ALSO *
REFERENCES * ^ A B Azar, K; Graebner J. E. (1996). "Experimental Determination
of Thermal Conductivity of Printed Wiring Boards". Proceedings of the
Twelfth IEEE SEMI-THERM Symposium: 169–182. doi
:10.1109/STHERM.1996.545107 .
* ^ A B Sarvar, F.; N. J. Poole; P. A. Witting (1990). "PCB
glass-fibre laminates:
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