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en:materialdaten:thermodynamische_daten [2024/07/16 14:26] – neelesten:materialdaten:thermodynamische_daten [2025/05/27 16:13] (aktuell) – neelest
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 ======Thermodynamic data====== ======Thermodynamic data======
  
-FIXME+===== Material data - Thermodynamics =====
  
-===== Thermodynamic Data =====+The rheological data of the material are entered in the ‘Thermodynamics’ tab: 
 +  * **Crystalline melting/glass transition temperature**: The crystallibe melting temperature (thermoplastic) corresponds to the temperature of the peak of the enthalpy curve. The glass transition temperature (amorphous plastic) corresponds to the temperature at which the amorphous plastic changes from a rigid, amorphous state to a soft state.  
 +  * **Thermal conductivity**: The thermal conductivity of the solid $\lambda_F$ is assumed to be constant. The thermal conductivity of the melt is specified for a value extrapolated to 0 °C ($\lambda_0$) with a gradient of $\lambda_m$ per 1 °C. 
 +  * **Molecular structure**: For semi-crystalline thermoplastics, a distinction is made between solids enthalpy and melting enthalpy. In the case of amorphous plastics, there is only an enthalpy of solids. 
 +  * **Specific heat capacity**: This is only required for the melt. It is modelled as a straight line with a constant gradient with a value extrapolated to 0 °C ($c_{p,0}$) and a gradient of $c_{p,m}$ per 1 °C. 
 +  * **Melting enthalpy**: The enthalpy for melting the crystalline areas (only partially crystalline plastics) 
 +  * **Solids enthalpy**: The enthalpy up to the crystalline melting/glass transition temperature, which is required for heating
  
-**Platzhalter Abbildung 5.12: Eingabemaske thermodynamische Daten**+{{ :materialdaten:rex171_mat_en_002.png?nolink |}}
  
-==== Specific Heat Capacity ====+===== Theoretical principles =====
  
-The function curve of the specific heat capacity $c_p$ at ambient pressure for +==== Thermal conductivity ==== 
-amorphous and semi-crystalline thermoplastics is shown in the following figure. In the + 
-melting range the specific heat capacity follows a virtually linear course and can thus +\[λ(T) = λ_0 + λ_m \cdot T\] 
-be described by a straight-line equation: + 
 +$λ_0$ represents the thermal conductivity resulting from the straight line describing the melt range at 0 °C. The gradient of the thermal conductivity $λ_m$ can also be negative and must then be entered with a negative sign. The effective thermal conductivity of the solid is required for the melting calculation. To determine this value, the thermal conductivity of the solid $λ_F$ must be entered. 
 + 
 +{{ :materialdaten:abb_warmeleitfaehigkeit_en.svg?nolink&700 |}} 
 +==== Specific heat capacity ====  
 +The function curve of the specific heat capacity $c_p$ at ambient pressure is shown for amorphous and semi-crystalline thermoplastics in the following figure. In the melt range, the specific heat capacity behaves almost linearly and can therefore be calculated using a linear equation: 
  
 \[c_p(T) = c_{p,0} + c_{p,m}\cdot T\] \[c_p(T) = c_{p,0} + c_{p,m}\cdot T\]
  
-{{ :materialdaten:abb_waermekapazitaet_en.svg |}}+The peak in the curve for semi-crystalline thermoplastics describes the temperature $T_K$ and thus the melting temperature. 
 + 
 +{{ :materialdaten:abb_waermekapazitaet_en.svg?nolink&700 |}}
  
 ==== Specific Enthalpy ==== ==== Specific Enthalpy ====
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 \[Δh = \int \limits_ {T_1}^{T_2} c_p(T)dT\] \[Δh = \int \limits_ {T_1}^{T_2} c_p(T)dT\]
  
-Thus, one obtains the quantity of heat expressed in terms of the mass unit, which is +This gives the amount of heat related to the unit mass that is required to increase the temperature of the polymer from $T_1$ to $T_2$.
-required to increase the temperature of the polymer from $T_1$ to $T_2$. In case of +
-amorphous materials, a steeper increase is seen in the temperature if the glass +
-transition point $T_g$ is exceeded. +
  
-By contrast, semi-crystalline materials show a +In contrast, semi-crystalline materials exhibit a step-like increase due to the phase transition. The additional amount of heat is referred to as the melting enthalpy $∆h_A$. The following figure shows the specific enthalpy as a function of temperature.
-stepwise increase on account of the phase change. The additional quantity of heat is +
-described as the melting enthalpy $∆h_A$. The following figure shows the specific enthalpy as a +
-function of temperature.+
  
-With indicating **amorphous thermoplastics** the field for melting enthalpy is not +{{ :materialdaten:abb_enthalpie_en.svg?nolink&700 |}}
-editable. In case of **semi-crystalline thermoplastics** the increase in enthalpy $∆h$ is +
-formed by an enthalpy increase of the solid material $∆h_F$ and the melting enthalpy +
-$∆h_A$ : +
  
-Amorphous thermoplastics: \[∆h=∆h_F\]+When specifying an **amorphous thermoplastic**, the field for the melting enthalpy is not editable. For **semi-crystalline thermoplastics**, the enthalpy increase $∆h$ consists of the enthalpy increase of the solid phase $∆h_F$ and the melting enthalpy $∆h_A$:
  
-Semi-crystalline thermoplastics: \[∆h=∆h_F+ ∆h_A\] +Amorphous thermoplastics: \[∆h_{T_G}=∆h_F\]
- +
-{{ :materialdaten:abb_enthalpie_en.svg |}} +
- +
-==== Thermal Conductivity ==== +
- +
-In the case of thermal conductivity, it is necessary to distinguish between steadystate and non-steady-state temperature fields. With steady-state temperature fields +
-only the thermal conductivity $λ$ is available as a material value. This is +
-temperature-dependent and higher for semi-crystalline materials than for amorphous +
-ones.  +
- +
-\[λ(T) = λ_0 + λ_m \cdot T\]+
  
-$λ_0$ represents the value obtained from the straight line that describes the +Semi-crystalline thermoplastics: \[∆h_{T_K}=∆h_F+ ∆h_A\]
-melt range at 0 degrees. The gradient for the thermal conductivity $λ_m$ +
-can also be negative and must then be entered with a negative sign. The effective +
-thermal conductivity of the solid is required for the melting calculation. In order to +
-determine this value it is necessary to enter the thermal conductivity of the solid $λ_F$. The melting temperature $T_{k,g}$ must be entered in this mask. In the case +
-of semi-crystalline materials this temperature is interpreted as the crystalline melting +
-point $T_k$ and in case of amorphous polymers as the glass transition point $T_g$. +
  
-{{ :materialdaten:abb_warmeleitfaehigkeit_en.svg |}}+Plus the enthalpy increase in the melting range: $$∆h_{melt}=\frac{1}{2} c_{p,m} \cdot (T^2-{T_{K,G}}^2) + c_{p,0} \cdot (T-T_{K,G})$$
  
  
 +===Further topics===
 +  * [[en:materialdaten:datenbankanbindung_an_pam|]]
 +  * [[en:materialdaten:allgemeineangaben|]]
 +  * [[en:materialdaten:thermodynamische_daten|]]
 +  * [[en:materialdaten:dichtedaten_bzw._spezifisches_volumen|]]
 +  * [[en:materialdaten:rheologische_materialdaten|]]
 +  * [[en:materialdaten:technologische_daten|]]
 +  * [[en:materialdaten:tribologische_daten|]]
 +  * [[en:materialdaten:zusatzstoffe|]]
 +  * [[en:materialdaten:molekulargewicht|]]
 +  * [[en:materialdaten:faserabbau|]]
 +  * [[en:materialdaten:eingabe_von_mischungen|]]