The use of lightweight materials in the production of cryogenic tanks, spacecraft body etc. are becoming the need to develop dissimilar metal FSW joints. Friction stir welding (FSW) is a novel and inspired light metal joining process since it is not involved with the melting of the parent metal. In this work, two Aluminium 7020 plates were welded with Zn as an interlayer, using friction stir welding method. Different joints were made by varying the thickness of interlayer (Zn) and thereafter the characterization is done against mechanical properties and microstructure of weld nugget. The test result shows that the specimen joint with 10μ Zn interlayer has higher mechanical properties than samples made with 5μ, 10μ, 20μ, 40μ and 100μ Zn interlayer. To analyze the cause, further optical studies (Image analyzer and SEM analysis) were carried out and found the interlayer dispersion plays a vital role in weld strength. As a conclusion addition of Zinc interlayer with preferable thickness (10μ) in Al7020 FSW joints improve tensile strength and hardness than the FSW joints made with higher and lower interlayer thickness.

O extrato aquoso de folhas de Prosopis cineraria (AEPC) é utilizado, tradicionalmente, para o tratamento de várias disfunções do SNC. O propósito desse estudo foi avaliar o extrato quanto às atividades antidepressiva e relaxante muscular esquelética. O efeito antidepressivo do extrato foi avaliado usando o teste do nado forçado (FST). Registraram-se os períodos de imobilidade dos camundongos controle e dos tratados. O efeito antidepressivo do composto testado foi comparado com a imipramina ((15 mg/kg. p.o). A propriedade relaxante muscular foi estudada usando o cilindro giratório e o tempo total de queda para os grupos padrão e controle foram registrados. A triagem fitoquímica revelou a presença de saponinas, flavonoides, alcaloides, glicosídeos, taninos e compostos fenólicos. O extrato da folha em doses de 200 mg/kg diminui significativamente a duração do tempo de imobilidade no FST. A eficácia do extrato testado foi comparável àquela da imipramina. Nossos resultados sugeriram que o extrato aquoso das folhas da Prosopis cineraria exerce efeito semelhante ao antidepressivo.

The aqueous leaves extract of Prosopis cineraria (AEPC) is used traditionally for the treatment of various CNS disorder. The purpose of this study was to evaluate the extract for antidepressant and skeletal muscle relaxant activity. The antidepressant effect of the extract was evaluated using Forced swim test (FST). The immobility periods of control and treated mice were recorded. The antidepressant-like effect of tested compound was compared to that of imipramine (15 mg/kg. p.o). Muscle relaxant property was studied using rotarod apparatus and total fall off time for standard and control group was recorded. Phytochemical screening revealed the presence of saponins, flavonoids, alkaloids, glycosides, tannins and phenolic compounds. The leaf extract at doses of 200 mg/kg significantly decreased the duration of immobility time in FST. The efficacy of tested extract was found to be comparable to that of imipramine. Our results suggested that the aqueous extract of Prosopis cineraria leaves exerts antidepressant-like effect.