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A stochastic modelling framework is developed to predict the flexural properties of high-strength sheet moulding compounds made of randomly oriented ultra-thin carbon fibre-reinforced thermoplastic prepreg tapes. The model enables reliable designs using ultra-thin randomly oriented strands with less testing, leading to potential applications in automotive primary structures. The stochastic model is based on a Monte Carlo simulation. The flexural modulus is predicted using classical laminate theory, while the flexural strength is predicted by following a Weibull distribution. Fibre discontinuities are considered through stress concentrations introduced by tape overlaps. The results are validated against new 3-point bending and previously reported 4-point bending experimental results. A scaling effect on strength and scatter is predicted, and its implications for structural applications are also discussed. [ABSTRACT FROM AUTHOR]

Supercritical carbon dioxide dewatering (SCD) offers significant potential for wood treatment due to its unique physical-chemical properties. SCD has the advantage of avoiding drying defects caused by capillary tension during the removal of free water in conventional kiln drying (CKD). In this study, 150 mm-long specimens of Juglans mandshurica wood underwent both SCD and CKD treatments, allowing for comparison of various dewatering characteristics such as dewatering rate, moisture distribution, deformation, and drying stresses. The findings revealed that the optimal dewatering time was 25 min. SCD proved highly effective, especially during the high moisture content (MC) phase, demonstrating a dewatering rate up to 5.6 times faster than CKD. SCD achieved a more even dewatering process across the wood, with a maximum MC difference of 4.52% between the core and surface zones. In contrast, CKD exhibited an MC difference 8.3 times larger than SCD. Furthermore, in the longitudinal direction, CKD displayed lower MC at the wood's end locations compared to SCD. Additionally, wood showed shrinkage following CKD but swelling after SCD treatment. Interestingly, both SCD and CKD treatments resulted in nearly identical drying stresses. [ABSTRACT FROM AUTHOR]