README
======

Dataset title:
Data for Dielectric Breakdown Strength of Unidirectional Fiber Composites: Weibull Analysis of Fiber Orientation and Size Effects

Recommended Citation:  
Arvidsson, K., Ranathunga Arachchige, I. A. U., & Fernberg, P. (2025). Data for: Dielectric Breakdown Strength of Unidirectional Fiber Composites: Weibull Analysis of Fiber Orientation and Size Effects (Version 1) [Dataset]. Luleå University of Technology. Available via: https://doi.org/10.5878/n7kd-dh47
See the Researchdata.se catalogue entry for this dataset - accessible via the DOI link above - for compete metadata, including the dataset description, contact information and information about how to obtain the dataset. 

Responsible organization:
Luleå University of Technology 
Department of Engineering Sciences and Mathematics

Description: The dataset contains experimental data from dielectric strength testing of unidirectional glass fiber–epoxy composites. 

Access restrictions: This dataset can be requested from the Researchdata.se research data catalog using the link above.

Essential information for dataset reuse.
----------------------------------------
The dataset contains experimental data from dielectric strength testing of unidirectional glass fiber–epoxy composites. The composite laminates were manufactured by pressing prepregs and exhibited low porosity.
Tests were performed in a Phenix 6CC100-5/D149 under alternating voltage according to ASTM D149-20. Electrodes and specimen were submerged in transformer oil to prevent surface flashover. 
Flat, parallel electrodes covering the entire specimens were used to apply a continuously increasing potential difference, corresponding to an electric field increase of 0.25 (kV/mm)/s.
Samples with varying fiber angles relative to the applied electric field (0°, 30°, 45°, 60°, 90°), electrode gaps (2 mm, 4 mm, 8 mm, 16 mm), and cross-sectional areas (30 mm², 50 mm², 70 mm²) were tested.
Specimens for which a clearly carbonized breakdown path in the material could not be visually identified after the first test were subjected to a second test.

Datafile descriptions
----------------------

Dielectric_Breakdown_Strength_of_Unidirectional_Fiber_Composites_Fiber_Orientation_and_Size_Effects.xlsx 
Worksheets:
	Material_database. Contains information about the manufactured laminates from which specimens are cut. Each laminate has a unique Material ID (mXXX), which is also included as part of the Specimen ID.
	Specimen_database. Contains information about the specimens used for testing.  Each specimen has a unique ID in the format mXXX-sXXX, where the Material ID (mXXX) indicates the laminate from which the specimen was taken.
		L [mm]: In-plane length of the specimen. Together with t, it defines the cross-sectional area in the dielectric strength testing setup, which is oriented perpendicular to the externally applied electric field.
		t [mm]: Out-of-plane thickness of the specimen. Together with L, it defines the cross-sectional area in the dielectric strength testing setup, which is oriented perpendicular to the externally applied electric field.
		d [mm]: In-plane width of the specimen. This dimension equals the electrode gap distance and is aligned with the externally applied electric field in the dielectric strength testing setup.
	Tests. Contains information about each individual test. The defined test method is specified in sheet 'Test_methods'. The surrounding material is specified in sheet 'Surrounding_materials'.
	Test_methods. Lists parameters and settings for different test methods/programs.
	Surrounding_materials. Provides information about the material surrounding the electrodes and the specimen, used to prevent surface flashover.

Reference information
---------------------

Data Quality:
Results were automatically recorded by the test machine and the data were added to the database by a script to avoid manual mistakes. All tests were video recorded to enable visual inspections of outliers. No test results were discarded. 

