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This experiment was performed to investigate the effect of foliar application of amino acids on improving biochemical properties and yield evaluation of the effect of drought stress on pistachio, cv. Shahpsand in Damghan city during 2019 and 2020. Statistical analysis was conducted as a factorial split-plot based on a randomized complete block design (RCBD) with three replications. The main factor was irrigation intervals (35, 55, and 75 days) and sub-factors were including asparagine and glutamine amino acids at three levels (0, 150 and 300 mg L-1). The results showed that the irrigation interval had a significant effect on catalase, peroxidase, polyphenol oxidase, sodium, chlorine, potassium, proline, protein, relative water content (RWC), and yield at the level of 1% probability and the maximum content of catalase, peroxidase, polyphenol oxidase, chlorine, proline, and RWC were observed at 75 days irrigation interval but the highest yield and potassium were obtained at 35 days irrigation interval. Mineral concentrations of sodium (Na) and chloride (Cl), in leaves increased with increasing irrigation cycle however, the Potassium (K) concentration in leaves decreased. The highest Na concentrations and Cl were observed in 75 days, and the lowest was in 35days. The correlation coefficient between catalase and peroxidase was positive and the correlation between sodium and potassium was Negative, but the correlation between chlorine and protein was negative. Foliar application of amino acids increased plant yield and resistance to drought stress.

Nowadays, industrial demands on materials with high strength and superior physical properties have made ultra-fine grain metallic materials one of the hot topics for materials science studies. In the present study, the newly developed technique based on severe plastic deformation so-called Repetitive Corrugation and Straightening by Rolling (RCSR) was applied to study its effect on the microstructure and mechanical behavior of commercially pure aluminum. The microstructure and correlated mechanical behavior of specimens after RCSR was systematically studied. A polymodal microstructure as revealed by the microstructural studies, and high elongation with relative good strength after RCSR indicate promising results. Our studies show that the heterogeneous mode of deformation in RCSR could be responsible for the poly-modal microstructure that along with the proper evolution of texture components gives the material both high ductility and reasonable strength. In fact, the combination of RCSR performance and the physicomechanical properties of aluminum provide the opportunity to get outstanding tensile properties without any subsequent annealing process.

Texture evolution in a newly developed severe plastic deformation technique, named multi-axial incremental forging and shearing (MAIFS), was studied applying the visco-plastic self-consistent crystal plasticity formulation by consideration of macroscopic deformation history. The simulated texture evolutions revealed that although shear-like texture had developed by the MAIFS process, texture components rotated around normal to mid-plane section. This could be ascribed to the complex deformation history that naturally develops during processing by the MAIFS process. The increased complexity of the deformation history in the MAIFS process, compared to the techniques that are solely based on the simple shear deformation, causes more activated slip planes, which in turn can result in an enhanced grain refinement ability of this processing technique.

A novel severe plastic deformation (SPD) technique entitled Multi-Axial Incremental Forging and Shearing (MAIFS) has been introduced and the preliminary evaluation of this technique by characterizing the material flow has been described in this paper. The MAIFS process is the combination of incremental forging (or incremental back extrusion) followed by angular pressing. The streamline visualized data of a tin-based alloy as the representative of the soft deformable metals was utilized to predict the strain distribution experienced by material during deformation induced by MAIFS process. It was demonstrated that acceptable deformation homogeneity can be achieved after pass two of the process, and the workpieces were deformed up to four passes of MAIFS without any crack or discontinuity. The first results of numerical simulations of proposed process after four consecutive passes proved its general feasibility, and comparison of acquired data with the simulation results of same specimen processed by four passes ECAP through route Bc confirmed the capability of MAIFS process. An attempt has also been made to primarily investigate the potential of the process for grain refinement.

A new design of billet, based on a core–sheath configuration, was used for the processing of Ni, Fe, and a NiTi alloy by equal-channel angular pressing (ECAP) at room temperature. This configuration involves inserting metal cores within Fe sheaths prior to processing and it is designed especially for use with hard-to-deform materials. Billets were processed through one or two ECAP passes at room temperature and the microhardness values were recorded across the transverse directions within the cores to evaluate the flow process. As in conventional ECAP, the hardness increased significantly after the first pass and there were regions of lower hardness along the bottom surfaces of each core. The gradient of hardness decreased with increasing core diameter but the average microhardness values remained unchanged. Three-dimensional finite element simulations were used to evaluate the flow behavior after one pass of ECAP using different core metals. These simulations show the lower areas of the cores undergo less deformation than the upper areas and the homogeneity increases with increasing levels of friction at the core–sheath interface.