> For the complete documentation index, see [llms.txt](https://dante-solutions-inc.gitbook.io/dante-6.3-help-documentation/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://dante-solutions-inc.gitbook.io/dante-6.3-help-documentation/readme/material-database/material-model-control-file-dctrla.md).
# Material Model Control File (DCTRLA)
A control file is included in each release, located in the \DANTE\version\DCTRLA\ subdirectory.
The DCTRLA.CTL file is keyword based, contains parameters to control the maximum changes of certain variables and to allow the activation or deactivation of optional DANTE models. The DCTRLA file parameters and models are used by **ALL** DANTE models, unless a DCTRLA file is included in the model’s working directory. This is in contrast to the material specific control file, which controls models at the material level. The DANTE software will check for a DCTRLA file in the working directory and, if one is present, will use any parameters and/or models defined there. The software will then use the DCTRLA file in the DCTRLA subdirectory to determine the values for any undefined models or parameters.
*Figure: DCTRLA.CTL file located in the DANTE material database.*
**Summary of Control Keyword Priority Order:**
1. Current Working Directory: If the keyword is defined in the **DCTRLA.CTL** file in the current working directory, its value will be used. Otherwise check next -->
2. Installation Directory: **/DANTE/version/DCTRLA/DCTRLA.CTL** file, the keyword values defined in this file will be used. Otherwise check next -->
3. Material Data: In each material data directory, there is a **\*.CTL** file. For example, **S41XX.CTL**. The keyword values defined in this file will be used.
4. If the keyword value is not defined in any of the above three options, a default value will be given.
5. The actual values for the important keywords are written in the model model **\*log** file for reference.
An example of DCTRLA.CTL file is shown below.
```
** File Name: DCTRLA.CTL for Model and Control Defaults
** '*' indicates a keyword and is used by the software
** '**' indicates a comment line and is ignored by the software
**
**
******* Maximum changes allowed for various variables ********
**DTEMP_MAX; maximum temperature change in one increment (default 30.0)
*DTEMP_MAX
30.0
** DPHAS_MAX; maximum volume fraction (VF) phase change in one increment (default: 0.20)
*DPHAS_MAX
0.20
**DCRB_MAX; maximum carbon change in one increment (default: 0.0005)
*DCARB_MAX
0.00050
** DNTRG_MAX; maximum nitrogen change in one increment (default: 0.0001)
*DNTRG_MAX
0.00010
** DPHASP_MAX; maximum VF of precipitate (PPT) change in one increment (default: 0.001)
*DPHASP_MAX
0.0010
** DGRWTHP_MAX; maximum PPT size class growth in one increment (default: 0.5 spacing)
*DGRWTHP_MAX
0.5
**
**
**
******** Select Models to Activate/Deactivate ********
**** BEWARE: ACTIVATION OF A MODEL IN THIS FILE WILL NOT ****
**** ALLOW THAT MODEL TO BE CHANGED IN THE MATERIAL .CTL FILE ****
** Hardness Unit: IFLG_HARD (1: HV; 0: HRC/Default)
** This flag can be ONLY set to 1 in this DCTRLA file, if nececcsay
** In the MAT*CTL file, the hardness can only be specified as HRC (value=0)
*IFLG_HARD
0
***IFLG_KIN
**-4
***IFLG_LHEAT
** 0
***IFLG_CBDCOMP
** 0
***IFLG_CPRCIP
** 1
***IFLG_APRCIP
** 0
***IFLG_CREEP
** 0
***IFLG_STSRLX
** 0
***IFLG_LIQUID
** 0
```
***DCTRLA CONTROL FILE KEYWORD DESCRIPTIONS:***
***\*DTEMP\_MAX***: Sets the maximum temperature change, in °C, allowed for a single timestep (substep) in the analysis. The default value of 30° C is sufficient for most analyses. This value can be reduced to aid in temperature, phase transformation, stress, or displacement related convergence issues.
***\*DPHAS\_MAX***: Sets the maximum phase transformation change, in volume fraction, allowed for a single timestep (substep) in the analysis. The default value of 0.2 is sufficient for most analyses. This value can be reduced to aid in phase transformation, stress, or displacement related convergence issues.
***\*DCARB\_MAX***: Sets the maximum carbon change, in weight fraction, allowed for a single timestep (substep) in the analysis. The default value of 0.0005 is sufficient for most analyses. This value can be reduced to aid in carbon related convergence issues.
***\*DNTG\_MAX***: Sets the maximum nitrogen change, in volume fraction, allowed for a single timestep (substep) in the analysis. The default value of 0.0001 is sufficient for most analyses. This value can be reduced to aid in nitrogen related convergence issues.
***\*SPHASP\_MAX***: Sets the maximum precipitate change, in volume fraction, allowed for a single timestep (substep) in the analysis. The default value of 0.001 is sufficient for most analyses. This value can be reduced to aid in precipitation related convergence issues.
***\*DGRWTHP\_MAX***: Sets the maximum precipitate size change, in DANTE size class, allowed for a single timestep (substep) in the analysis. The default value of 0.5 is sufficient for most analyses. This value can be reduced to aid in precipitation growth related convergence issues.
***\*IFLG\_KIN***: Sets the default phase transformation kinetics mode. If the Phase Transformation Kinetics Mode (1st field variable) is not set in the input file, or is left as ‘default’ in Model Control using the DANTE Plug-In, the value assigned to this keyword will be used. Otherwise, it will be overwritten by the value defined in the input file or Plugin.
* Flags: -4 (Default), -5, -6, -7, -8, -9, -10, and -11. Please see the Phase Transformation Kinetics Mode section for a detailed description of each mode.
***\*IFLG\_LHEAT***: Model used to describe the effect of latent heat that is released during the transformation of austenite to ferrite, pearlite, upper bainite, lower bainite, and martensite. The latent heat absorbed during the transformation to austenite can also be modeled. The latent heat is modeled to capture any variation in the heating or cooling rate which would affect the timing of phase transformations.
* Flags: 2 = Activated for Heating and Cooling; 1 = Activated for Cooling Only; 0 = Not Activated (Default)
***\*IFLG\_CBDCOMP***: Model used to describe the decomposition of carbides at high temperature into the austenite matrix. Time is required to decompose carbon from carbide form into the austenitic matrix and therefore this model can be used to help determine the optimum soaking time during austenitization. Carbides can be formed during the steel manufacturing process or from a carburization process. This model is used in the DANTE Thermal and Stress Models, not the Carburization Model. This parameter will automatically be activated to maintain model cohesion if \*IFLG\_CPRCIP and/or \*IFLG\_APRCIP are activated.
* Flags: 1 = Activated (Default); 0 = Not Activated
***\*IFLG\_CPRCIP***: Model used to describe the precipitation and coarsening of iron carbides during a tempering process. As-quenched martensite transitions to tempered martensite by rejecting carbon which was trapped in the supersaturated ferritic matrix from rapid cooling. The rejected carbon combines with iron to form iron carbides. If \*IFLG\_CPRCIP is activated, \*IFLG\_CBDCOMP is automatically activated to ensure all carbide models remain cohesive and the behavior is accurately modeled.
* Flags: 1 = Activated (Default); 0 = Not Activated
***\*IFLG\_APRCIP***: Model used to describe the precipitation and coarsening of alloy carbides during a tempering process. After carbon is rejected from the supersaturated matrix, it forms iron carbides. Some steel alloys will then undergo a secondary hardening, by which the carbon dissociates from the iron and combines with alloy elements to form alloy carbides. If \*IFLG\_APRCIP is activated, \*IFLG\_CBDCOMP is automatically activated to ensure all carbide models remain cohesive and the behavior is accurately modeled.
* Flags: 1 = Activated; 0 = Not Activated (Default)
***\*IFLG\_CREEP***: Model used to describe material creep occurring during relatively long times. This model is intended to capture the effects of long-term creep.
* Flags: 1 = Activated; 0 = Not Activated (Default)
***\*IFLG\_STSRLX***: Model used to describe the stress relaxation occurring at higher temperatures and relatively shorter times. This model is not intended to capture the effects of long-term creep.
* Flags: 1 = Activated; 0 = Not Activated (Default)
***\*IFLG\_LIQUID***: Model used to describe the latent heat released as the steel transforms from a liquid state to a solid state and the latent heat absorbed as the steel transforms from a solid to a liquid. This model is useful when simulating additive manufacturing processes, welding processes, cladding processes, or any process where the steel may transform between its solid and liquid states.
* Flags: 1 = Activated; 0 = Not Activated (Default)
---
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