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This research aims to study the fracture behaviour in dissimilar aluminum alloys adjoined by friction stir welding (FSW). In this way, experimental data dealing with this topic was taken from the recent literature. In those experimental results, two metal sheets made of Al 7075-T6 and Al 6061-T6 were adjoined together by FSW in the form of well-known specimen, namely the cracked semi-circular bend (CSCB) and then they are tested under mixed mode I/II loading condition. Due to the fact that substantial plastic behavior exist in the welded material and consequently significant plastic deformations were observed around the crack tip, failure prediction of the mentioned specimens needs failure prediction models in the basis of the elastic-plastic fracture mechanics which can be realized as sophisticated operations inquiring long time. In this way, the Equivalent Material Concept (EMC) is utilized in this research and then coupled with two eligible energy-based criteria, namely the averaged strain energy density (ASED) and J-integral criteria. Thus, the critical failure load of the welded samples is predicted. Comparison between the empirical data and theoretical predictions from energybased evaluations showed that this model has enough capability in estimating the critical failure load of the CSCB samples.

Drug delivery into the peripheral nerves and nerve roots has important implications for effective local anesthesia and treatment of peripheral neuropathies and chronic neuropathic pain. Similar to drugs that need to cross the blood–brain barrier (BBB) and blood–spinal cord barrier to gain access to the central nervous system (CNS), drugs must cross the peripheral nerve barriers (PNBs), formed by the perineurium and blood–nerve barrier to modulate peripheral axons. Despite significant progress made to develop effective strategies to enhance BBB permeability in therapeutic drug design, efforts to enhance drug permeability and retention in peripheral nerves and nerve roots are relatively understudied. Guided by knowledge describing structural, molecular, and functional similarities between restrictive neural barriers in the CNS and peripheral nervous system, it is hypothesized that certain CNS drug delivery strategies are adaptable for peripheral nerve drug delivery. Here, the molecular, structural, and functional similarities and differences between the BBB and PNB are described, existing CNS and peripheral nerve drug delivery strategies are summarized and compared, and the potential application of selected CNS delivery strategies to improve efficacious drug entry for peripheral nerve disorders is discussed.

The present research is focused on checking that if the EMC‐J criterion, which is a combination of Equivalent Material Concept (EMC) and the linear elastic J‐integral expression for blunt V‐notches, could be a suitable evaluation to estimate the critical load in ductile aluminum plates with V‐shaped notches subjected to tension loading, experiencing significant yielding regimes. To proceed, Al 7075‐T6 and Al 6061‐T6 rectangular thin plates with V‐shaped notches are considered based on the recent researches. Due to ductile behavior of the two aluminum alloys, utilization of EMC is necessary to get rid of elastic‐plastic calculations for theoretical estimations, which normally consume so much time and come with complexities. It is worth noting that this research is the first of its kind to estimate the failure load of the ductile specimens with V‐shaped notches subjected to tension by combining the EMC and linear elastic J‐integral for blunt V‐shaped notches. Finally, the evaluations of EMC‐J criterion for blunt V‐notches revealed that it can predict the experimental results of failure load well.