Dataset used in the publication entitled "Origin of nucleation and growth of extension twins in grains unsuitably oriented for twinning during deformation of Mg-1%Al"

Documentation for the Dataset used in the publication entitled "Origin of nucleation and growth of extension twins in grains unsuitably oriented for twinning during deformation of Mg-1%Al"** These datasets comprise the 2D data acquired in the Mg-1Al (at.%) alloy sample by means of in-situ EBSD, analyzed by MTEX 7.0 software. **** The samples were deformed in tension and the test was periodically stopped to acquire the data. The in-situ EBSD data were acquired at tensile strains of 1.5%, 4.5%, 10.0%, and 15.3%.** More details about the experimental techniques can be found in the publication "Biaobiao Yang, Javier Llorca, Origin of nucleation and growth of extension twins in grains unsuitably oriented for twinning during deformation of Mg-1%Al. Journal of Magnesium and Alloys, 2024." **

1. Figs.1(B)_and_2_Grainsize_SF_Dataset.xlsx- Description: The grain size and Schmid factors (SF) of various deformation modes acquired by in-situ EBSD before deformation- Number of total grains: 4251 (rows == grains)- Number of analyzed variables (features): 8 (columns == grain characteristics)

- Variable description by columns:        1- (Grain_ID) - type: numerical (integer)        Description: grain identifier, unique per analyzed zone        2- (Grain_size) - type: numerical (float)        Description: the equivalent circle diameter of a grain        3- (SF_Basal) - type: numerical (float)        Description: it represents the highest Schmid factor of basal slip in each grain        4- (SF_Prismatic) - type: numerical (float)        Description: it represents the highest Schmid factor of prismatic slip in each grain        5- (SF_ET) - type: numerical (float)        Description: it represents the highest Schmid factor of extension twinning (ET) slip in each grain        6- (SF_Pyramidal) - type: numerical (float)        Description: it represents the highest Schmid factor of pyramidal slip in each grain        7- (SF_Pyramidal) - type: numerical (float)        Description: it represents the highest Schmid factor of pyramidal I slip in each grain        8- (SF_CT) - type: numerical (float)        Description: it represents the highest Schmid factor of compression twinning (CT) in each grain

2. Fig.3(A)_Stress-strain_curves.xlsx- Description: The true tensile stress-true strain curve of Mg-1Al alloy deformed along the extrusion direction- Number of analyzed variables (features): 2 

- Variable description by columns:        1- (True_Strain) - type: numerical (float)        Description: True strain during deformation        2- (True_Stress) - type: numerical (float)        Description: True stress reached corresponding to given true strain

3. Fig.3(B)_Strain_Hardening-Rate-strain_curves.xlsx- Description: The strain hardening rate-true strain curve of Mg-1Al alloy deformed in tension along the extrusion direction- Number of analyzed variables (features): 2 

- Variable description by columns:        1- (True_Strain) - type: numerical (float)        Description: True strain during deformation        2- (Strain_Hardening-Rate) - type: numerical (float)        Description: Strain hardening rate at the given true strain

4. Fig.5_Features_anormalous_extension_twins.xlsx- Description: Both twin and grain data were acquired by in-situ EBSD before and after deformation- Number of total twins: 353 (rows == twins) in four sheets corresponding to four strains: 1.5%, 4.5%, 10.0%, and 15.3%.- Number of analyzed variables (features): 6 (columns == twin characteristics)

- Variable description by columns:        1- (Twin_ID) - type: numerical (integer)        Description: twin identifier, unique per analyzed zone        2- (Aspect ratio of twin) - type: numerical (float)        Description: the length / width ratio of twin. More details can be found on the MTEX website (https://mtex-toolbox.github.io/grain2d.aspectRatio.html)         3- (Twinned area fraction) - type: numerical (float)        Description: it represents the area fraction of one twin in the corresponding parent grain. The value of 1 indicates that the full parent grain is occupied by this twin        4- (Twinning Schmid factor) - type: numerical (float)        Description: the twinning Schmid factor based on the loading condition, orientation of the parent grain and twinning variants information        5- (Twin variants) - type: numerical (integer)        Description: the active twin variant was identified by means of conventional twinning analysis based on the orientations of twin and corresponding parent grain                1: (ET1)  (-1 0 1 2)[1 0 -1 1]                2: (ET2)  (1 0 -1 2)[-1 0 1 1]                3: (ET3)  (1 -1 0 2)[-1 1 0 1]                4: (ET4)  (-1 1 0 2)[1 -1 0 1]                5: (ET5)  (0 1 -1 2)[0 -1 1 1]                6: (ET6)  (0 -1 1 2)[0 1 -1 1]        6- (Twin variant Schmid factor ranking) - type: numerical (integer)        Description: the twinning Schmid factor ranking of active twin variant among 6 possible twin variants; the Schmid factor decreased from 1 to 6                1: 1st (the highest Schmid factor for extension twinning)                2: 2nd                3: 3rd                4: 4th                5: 5th                6: 6th (the lowest Schmid factor for extension twinning)

5. Fig.8(A)_Twin_twin_m_prime.xlsx- Description: Both twin and grain data were acquired by in-situ EBSD before and after deformation up to 10.0%- Number of twin-twin pairs: 17 (rows)- Number of analyzed variables (features): 12 (columns)

- Variable description by columns:         1- (Twin1_ID) - type: numerical (integer)        Description: the ID of the incoming twin of one twin-twin pair. Note that for one twin-twin pair, the twin with a higher macroscopic twinning Schmid factor is considered to be the incoming one        2- (Grain1_ID) - type: numerical (integer)        Description: the ID of parent grain nucleating the incoming twin        3- (Twin1_SF) - type: numerical (float)        Description: the twinning Schmid factor of incoming twin based on the loading condition, orientation of parent grain and twinning variants information        4- (Twin1_variant) - type: numerical (integer)        Description: the active twin variant was identified  by means of conventional twinning analysis based on the orientations of the twin and corresponding parent grain                1: (ET1)  (-1 0 1 2)[1 0 -1 1]                2: (ET2)  (1 0 -1 2)[-1 0 1 1]                3: (ET3)  (1 -1 0 2)[-1 1 0 1]                4: (ET4)  (-1 1 0 2)[1 -1 0 1]                5: (ET5)  (0 1 -1 2)[0 -1 1 1]                6: (ET6)  (0 -1 1 2)[0 1 -1 1]        5- (Twin2_ID) - type: numerical (integer)        Description: the ID of outgoing twin of one twin-twin pair        6- (Grain2_ID) - type: numerical (integer)        Description: the ID of parent grain nucleating the outgoing twin        7- (Twin2_SF) - type: numerical (float)        Description: the twinning Schmid factor of the outgoing twin        8- (Twin2_variant) - type: numerical (integer)        Description: the ranking of active outgoing twin systems with the same definition as column 4        9- (Theoretical m prime) - type: numerical (float)        Description: the m prime values between the grain with the incoming twin variant and 6 possible twin variants in grain having the outgoing twin         10- (GB misorientation angle) - type: numerical (float)        Description: the grain boundary misorientation (i.e., disorientation angle) angle between grains activating incoming and outgoing twins. The unit is degree        11- (True m prime) - type: numerical (float)        Description: the m prime values between the grain with the incoming twin variant and the grain with the outgoing twin variant        12- (m prime ranking_Active twin) - type: numerical (integer)        Description: the m prime ranking of active twin among 6 values of theoretical m primes                1: 1st (the highest m prime)                2: 2nd                3: 3rd                4: 4th                5: 5th                6: 6th (the lowest m prime)

6. Fig.8(B)_Slip_twin_m_prime.xlsx- Description: Both twin and grain data were acquired by in-situ EBSD before and after deformation up to 10.0%. The active slip system was identified by slip traces - modified lattice rotation (ST-MLRA). - Number of slip-twin pairs: 84 (rows)- Number of analyzed variables (features): 8 (columns)

- Variable description by columns:         1- (Parent grain_ID) - type: numerical (integer)        Description: the ID of parent grain nucleating the extension twin         2- (Twin SF) - type: numerical (float)        Description: the twinning Schmid factor of the active twin. Note that several extension twins may exist in one grain, so there are several instances of the same grain ID but different twins in the database        3- (Twin variant) - type: numerical (integer)        Description: the active twin variant was identified by means of conventional twinning analysis based on the orientations of the twin and corresponding parent grain                1: (ET1)  (-1 0 1 2)[1 0 -1 1]                2: (ET2)  (1 0 -1 2)[-1 0 1 1]                3: (ET3)  (1 -1 0 2)[-1 1 0 1]                4: (ET4)  (-1 1 0 2)[1 -1 0 1]                5: (ET5)  (0 1 -1 2)[0 -1 1 1]                6: (ET6)  (0 -1 1 2)[0 1 -1 1]        4- (Neighboring grain_ID) - type: numerical (integer)        Description: the ID of neighboring grain near the appeared extension twin         5- (SF_basal) - type: numerical (float)        Description: the Schmid factor of active basal slip system identified by ST-MLRA for the neighboring grain        6- (Active_Basal slip) - type: numerical (integer)        Description: the active basal slip system identified by ST-MLRA for the neighboring grain                1: (S1)  (0 0 0 1)[-2 1 1 0]                2: (S2)  (0 0 0 1)[1 1 -2 0]                3: (S3)  (0 0 0 1)[1 -2 1 0]        7- (Theoretical m prime) - type: numerical (float)        Description: the m prime values between the neighboring grain with the active basal slip system and 6 possible twin variants in grain having the active twin         8- (True m prime) - type: numerical (float)        Description: the m prime values between the neighboring grain with the active basal slip system and the grain with the active twin variant

7. Figs.8(C-D)_Correlation_twin_grainArea_basalSlipSF.xlsx- Description: Summary of grain size, max. basal slip Schmid factor for all 555 grains before deformation, as well as the IDs of twinned grains after 1.5% and 10.0% tension- Number of grains: 555 (rows) for all grains- Number of analyzed variables (features): 5 (columns)

- Variable description by columns:         1- (Grain_ID) - type: numerical (integer)        Description: the IDs of all grains before deformation         2- (Grain_size) - type: numerical (float)        Description: the equivalent circle diameter of all the grains before deformation         3- (Max. Basal slip SF) - type: numerical (float)        Description: the maximum of basal slip Schmid factor for all the grains before deformation        4- (Grain_ID_1.5%) - type: numerical (integer)        Description: the IDs of all twinned grains after deformation up to 1.5%        5- (Grain_ID_10.0%) - type: numerical (integer)        Description: the IDs of all twinned grains after deformation up to 10.0% 

8. Fig.11(A)_Grain_level_misorientation_angle.xlsx- Description: misorientation angles of several grains subjected to different strains 

9. Fig.11(B)_Grain_level_longitudinal_strain.xlsx- Description: Lengths as well as longitudinal strains of several grains subjected to different strains 

10. Fig.14_Raw_grain_length_and_Longitudinal_strain.xlsx- Description: Raw data regarding the characteristics of twinned grains at various strain levels.                The grain size shown here is defined as the equivalent circle diameter.                And the grain length along the tensile direction is defined by the product of pixel number of one grain and the step size (0.5 μm).                Note that for some unfortunate grains, their spatial locations are near the edge of EBSD before or after deformation, thus their size characteristics are unknown.                One additional untwined grain G132 shown in Fig. 9 was also included in this table. - Number of grains: 72 (rows) for all twinned grains; 67 grains after removing the twinned grains near the EBSD edge- Number of analyzed variables (features): 12 (columns)

- Variable description by columns:        1- (Twinned grains ID) - type: G (grain) + numerical (integer)        Description: The IDs of all twinned grains before deformation          2- (Near edge?) - type: text (str)        Description: Yes: grain near the edge; No: grain not near the edge        3- (Grain size (μm)) - type: numerical (float)        Description: The equivalent circle diameter (in micrometers) of the grain before deformation        4-8- Raw grain length along the tension direction (μm)) - type: numerical (float)        Description: Raw grain lengths along the tension direction (μm) before deformation and at various macroscopic strain levels        9-12- (Logitutational strain) - type: numerical (float)        Description: Logitutational strain along the tension direction after deformed to various strain levels

11. Raw EBSD files in .ctf- Description: 0-4 refer to 0%, 1.5%, 4.5%, 10.0% and 15.3%, respectively.