Damage mechanisms and fracture-process-zone evolution during Mode I delamination of autoclave- and vacuum-assisted oven-cured flax/epoxy composites - data

Description

This dataset supports the article “Damage mechanisms and fracture-process-zone evolution during Mode I delamination of autoclave- and vacuum-assisted oven-cured flax/epoxy composites”. It contains the raw data of the double cantilever beam (DCB) tests: force–displacement records, crack length and crack opening from digital image correlation (DIC), and acoustic emission (AE) events. Research Hypothesis: 1. The curing route changes laminate microstructure (thickness, constituent fractions), which may affect Mode I delamination resistance. 2. Crack-wake mechanisms, mainly fibre bridging, contribute to the rising resistance curve and can be detected by AE behind the advancing crack tip. Data Summary: The data are provided as an SQLite database (data.db) and as a ZIP archive with the same tables exported to CSV. They cover 12 DCB specimens, 6 per curing route, identified by ID (20240192–20240203), which links all tables. Each test consisted of loading to 5 mm, unloading and reloading at 5 mm/min to 50 mm. DIC and force data were recorded every 0.5 s (one step). Units are part of the column names (us = µs, uV = µV, eu = AE energy units). Table Overview: • specimens: ID and curing route (autoclave or oven) • DIC: per step: time tDICs, force forceN, opening displacement Umm, crack length Lcrackmm (empty where the crack tip was not detected) • crackOpening: opening wmm at 300 positions xmm per step (linked to DIC by ID and step) • AEevents: one row per AE event located from two sensors (channel 1 at low xmm, channel 2 at high xmm): arrival times time1s, time2s (AE clock), forceN, per-channel descriptors (A amplitude, R rise time, E energy, CNTS counts, ALIN linear amplitude, D duration, RMS, TRAI transient index; e.g. A1dB, A2dB), source position xmm and tDICs, the event time on the DIC clock, which links to DIC.tDICs The x coordinates (xmm) and crack length Lcrackmm share one origin, so xmm − Lcrackmm is the position relative to the crack tip. Data Coverage: • AE recorded for 5 specimens (autoclave 20240200, 20240202; oven 20240199, 20240201, 20240203) • No crackOpening for 20240200 • The DIC table ends early for 20240198 (654 s), 20240200 (574 s) and 20240203 (525 s; crackOpening continues to 720 s). Lcrackmm ends at 564 s (20240198) and 298 s (20240200) • Three AE events per specimen with tDICs < 0 were recorded at zero load before DIC started Interpretation and Use: The data allow force–displacement curves, crack growth and crack-opening profiles to be reconstructed and, with the geometry and material data given in the article, resistance curves to be recalculated. AE events can be linked to the DIC record in time (tDICs) and to the crack tip in space (xmm − Lcrackmm). Curing-route comparisons rest on 6 vs 6 specimens (mechanical data) and 2 vs 3 (AE).

Steps to reproduce

Described in the article in detail (Damage mechanisms and fracture-process-zone evolution during Mode I delamination of autoclave- and vacuum-assisted oven-cured flax/epoxy composites).

Institutions

• University of Ljubljana

  Ljubljana, Ljubljana
• Lappeenranta-Lahti University of Technology

  South Karelia, Lappeenranta

Categories

Licence