DOI: 10.5281/zenodo.6965147
title: Database of Uniaxial Cyclic and Tensile Coupon Tests for Structural Metallic Materials

description: <strong>Database of Uniaxial Cyclic and Tensile Coupon Tests for Structural Metallic Materials</strong> <strong>Background</strong> This dataset contains data from monotonic and cyclic loading experiments on structural metallic materials. The materials are primarily structural steels and one iron-based shape memory alloy is also included. Summary files are included that provide an overview of the database and data from the individual experiments is also included. The files included in the database are outlined below and the format of the files is briefly described. Additional information regarding the formatting can be found through the post-processing library (https://github.com/ahartloper/rlmtp/tree/master/protocols). <strong>Usage</strong> The data is licensed through the Creative Commons Attribution 4.0 International. If you have used our data and are publishing your work, we ask that you please reference both: this database through its DOI, and any publication that is associated with the experiments. See the Overall_Summary and Database_References files for the associated publication references. <strong>Included Files</strong> Overall_Summary_2022-08-25_v1-0-0.csv: summarises the specimen information for all experiments in the database. Summarized_Mechanical_Props_Campaign_2022-08-25_v1-0-0.csv: summarises the average initial yield stress and average initial elastic modulus per campaign. Unreduced_Data-#_v1-0-0.zip: contain the original (not downsampled) data Where # is one of: 1, 2, 3, 4, 5, 6. The unreduced data is broken into separate archives because of upload limitations to Zenodo. Together they provide all the experimental data. We recommend you un-zip all the folders and place them in one "Unreduced_Data" directory similar to the "Clean_Data" The experimental data is provided through .csv files for each test that contain the processed data. The experiments are organised by experimental campaign and named by load protocol and specimen. A .pdf file accompanies each test showing the stress-strain graph. There is a "db_tag_clean_data_map.csv" file that is used to map the database summary with the unreduced data. The computed yield stresses and elastic moduli are stored in the "yield_stress" directory. Clean_Data_v1-0-0.zip: contains all the downsampled data The experimental data is provided through .csv files for each test that contain the processed data. The experiments are organised by experimental campaign and named by load protocol and specimen. A .pdf file accompanies each test showing the stress-strain graph. There is a "db_tag_clean_data_map.csv" file that is used to map the database summary with the clean data. The computed yield stresses and elastic moduli are stored in the "yield_stress" directory. Database_References_v1-0-0.bib Contains a bibtex reference for many of the experiments in the database. Corresponds to the "citekey" entry in the summary files. <strong>File Format: Downsampled Data</strong> These are the "LP_&lt;N&gt;_Specimen_&lt;M&gt;_processed_data.csv" files in the "Clean_Data" directory. The &lt;N&gt; is the load protocol designation and the &lt;M&gt; is the specimen number for that load protocol and material source. Each file contains the following columns: The header of the first column is empty: the first column corresponds to the index of the sample point in the original (unreduced) data Time[s]: time in seconds since the start of the test e_true: true strain Sigma_true: true stress in MPa (optional) Temperature[C]: the surface temperature in degC These data files can be easily loaded using the pandas library in Python through: <pre><code class="language-python">import pandas data = pandas.read_csv(data_file, index_col=0)</code></pre> The data is formatted so it can be used directly in RESSPyLab (https://github.com/AlbanoCastroSousa/RESSPyLab). Note that the column names "e_true" and "Sigma_true" were kept for backwards compatibility reasons with RESSPyLab. <strong>File Format: Unreduced Data</strong> These are the "LP_&lt;N&gt;_Specimen_&lt;M&gt;_processed_data.csv" files in the "Unreduced_Data" directory. The &lt;N&gt; is the load protocol designation and the &lt;M&gt; is the specimen number for that load protocol and material source. Each file contains the following columns: The first column is the index of each data point S/No: sample number recorded by the DAQ System Date: Date and time of sample Time[s]: time in seconds since the start of the test C_1_Force[kN]: load cell force C_1_Déform1[mm]: extensometer displacement C_1_Déplacement[mm]: cross-head displacement Eng_Stress[MPa]: engineering stress Eng_Strain[]: engineering strain e_true: true strain Sigma_true: true stress in MPa (optional) Temperature[C]: specimen surface temperature in degC The data can be loaded and used similarly to the downsampled data. <strong>File Format: Overall_Summary</strong> The overall summary file provides data on all the test specimens in the database. The columns include: hidden_index: internal reference ID grade: material grade spec: specifications for the material source: base material for the test specimen id: internal name for the specimen lp: load protocol size: type of specimen (M8, M12, M20) gage_length__mm_: unreduced section length in mm avg_reduced_dia__mm_: average measured diameter for the reduced section in mm avg_fractured_dia_top__mm_: average measured diameter of the top fracture surface in mm avg_fractured_dia_bot__mm_: average measured diameter of the bottom fracture surface in mm fy_n__mpa_: nominal yield stress fu_n__mpa_: nominal ultimate stress t_a__deg_c_: ambient temperature in degC date: date of test investigator: person(s) who conducted the test location: laboratory where test was conducted machine: setup used to conduct test pid_force_k_p, pid_force_t_i, pid_force_t_d: PID parameters for force control pid_disp_k_p, pid_disp_t_i, pid_disp_t_d: PID parameters for displacement control pid_extenso_k_p, pid_extenso_t_i, pid_extenso_t_d: PID parameters for extensometer control citekey: reference corresponding to the Database_References.bib file yield_stress__mpa_: computed yield stress in MPa elastic_modulus__mpa_: computed elastic modulus in MPa fracture_strain: computed average true strain across the fracture surface c,si,mn,p,s,n,cu,mo,ni,cr,v,nb,ti,al,b,zr,sn,ca,h,fe: chemical compositions in units of %mass file: file name of corresponding clean (downsampled) stress-strain data <strong>File Format: </strong><strong>Summarized_Mechanical_Props_Campaign</strong> Meant to be loaded in Python as a pandas DataFrame with multi-indexing, e.g., <pre><code class="language-python">tab1 = pd.read_csv('Summarized_Mechanical_Props_Campaign_' + date + version + '.csv', index_col=[0, 1, 2, 3], skipinitialspace=True, header=[0, 1], keep_default_na=False, na_values='')</code></pre> citekey: reference in "Campaign_References.bib". Grade: material grade. Spec.: specifications (e.g., J2+N). Yield Stress [MPa]: initial yield stress in MPa size, count, mean, coefvar: number of experiments in campaign, number of experiments in mean, mean value for campaign, coefficient of variation for campaign Elastic Modulus [MPa]: initial elastic modulus in MPa size, count, mean, coefvar: number of experiments in campaign, number of experiments in mean, mean value for campaign, coefficient of variation for campaign <strong>Caveats</strong> The files in the following directories were tested before the protocol was established. Therefore, only the true stress-strain is available for each: A500 A992_Gr50 BCP325 BCR295 HYP400 S460NL S690QL/25mm S355J2_Plates/S355J2_N_25mm and S355J2_N_50mm