1. Resistivity
Note: Only isotropic materials are considered.
Note: Resistivity ρ (rho) is a linear function of
temperature.
The corresponding mathematical formula is:
ρ _{T}

Resistivity to be defined at a temperature T.
Linear function of the temperature for an isotropic or anisotropic
material. 
T _{REF}

Reference temperature. 
T 
T is the temperature for which the resistivity must be
computed. 
ρ _{REF}

Resistivity of the material at T _{REF} . 
a 
Temperature coefficient at T _{REF} . 
2. Thermal conductivity for all materials except gas and
liquid
The thermal conductivity is defined at a reference temperature
and is considered as constant for all thermal computations.
The reference temperature is then only a memo, to keep in mind
the temperature corresponding to the indicated thermal
conductivity.
Symbol

Definition

Unit

T _{ref}

Reference temperature (Tref) 
°C 
K _{ref}

Isotropic thermal conductivity at Tref W/K/m) 
W/K/m 
3. Specific heat variation versus temperature – For all
material except gas and liquid
The specific heat is defined at a reference temperature and is
considered as constant for all thermal computations.
The reference temperature is then only a memo, to keep in mind
the temperature corresponding to the indicated specific heat.
Symbol

Definition

Unit

T _{ref}

Reference temperature (Tref) 
°C 
C _{ref}

Specific heat at Tref (J/K/Kg) 
J/K/Kg 
4. Remanent induction of magnets
Note: Only isotropic magnet is considered.
Note: Remanent induction (Br) is a linear function of the
temperature.
The corresponding mathematical formula is:
Br _{T}

Remanent induction to be defined at a temperature T.
Linear function of the temperature for an isotropic or anisotropic
material. 
T _{ref}

Reference temperature. 
T 
T is the temperature for which the remanent induction must be
computed. 
Br _{ref}

Remanent induction of the magnet at T _{REF} . 
a 
Reverse temperature coefficient for Br at T _{REF}
. 
5. Intrinsic Coercivity
Note: Only isotropic magnet is considered.
Note: Intrinsic Coercivity (HcJ) is a linear function of the
temperature.
The corresponding mathematical formula is:
HcJ _{T}

Intrinsic Coercivity to be defined at a temperature T.
Linear function of the temperature for an isotropic or anisotropic
material. 
T _{ref}

Reference temperature. 
T 
T is the magnet temperature for which the Intrinsic Coercivity
must be computed. 
HcJ _{ref}

Intrinsic Coercivity of the magnet at T _{REF} . 
a 
Reverse temperature coefficient for Hcj at T _{REF}
. 