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In the present study, two newly developed non-equiatomic high entropy Al10Cr12Mn28Fe(50-x)Ni(x) alloys (x= 20 & 15 at%, namely: Ni20 & Ni15, respectively) are investigated. The studied HEAs were designed based on thermodynamic principles to maintain high ductility and improve strength. Ingots were prepared using arc-melting then microstructure examinations and mechanical properties for the as-cast alloys were done. The mechanical properties were enhanced for the as-cast material, compared with previously introduced HEAs of the same system, namely Al5Cr12Mn28Fe35Ni20, (Al5) and Al10Cr12Mn23Fe35Ni20, (Al10). Al10Cr12Mn28Fe30Ni20 (Ni20) HEA generally shows the highest compressive yield strength which was improved by ∼7% when compared with previously introduced Al10.

In the present study, non-equiatomic AlCrFeMn x−TiNi high-entropy alloys bearing cost-effective elements were developed in light of enhancing mechanical strength. The Al5Cr12Fe35Mn28Ni20 HEA was used as a reference. However, the HEA containing Ti (Ti-HEA) was designed with a composition of Al5Cr12Fe35Mn23Ni20Ti5. The microstructural characteristics were studied by X-ray diffraction, electron probe micro-analysis, and electron backscattering diffraction. Subsequently, the mechanical properties were determined using micro-hardness, tensile and compression tests. Whereas the Ti-free HEA displayed a single FCC structure, a multi-phase structure was observed in the Ti-HEA. The mechanical tests showed that the Ti element significantly enhanced the strength. The strengthening effect was more intense during compression loading as the Ti-HEA exhibited superior combination of compressive strength and ductility (2.35GPa at 50% strain without fracture).

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Sesame is an important crop for the production of oil especially in newly reclaimed lands of Egypt. A machine for pelleting the small and light sesame seeds was designed and constructed in a laboratory scale to change the shape and size of sesame seeds enlarging the seed by a pellet which more heavier, size and rounder to facilitate sowing sesame seeds by planters. Some of the most important operational parameters were investigated, whereas, rotating speed of the pelleting pan affected the physical pellet properties. Rotating speed of 30 rpm showed the greatest pellet weight, sphericity percentage and true density. Out of three different quantities (100, 250 and 500g) of seeds per run during pelleting process, 250 g showed maximum pellet axial dimensions, pellet volume and weight. Ratio between pelleting material added to the pan during run and seed quantity was considered, whereas, ratios of 5:1, 10:1 and 20:1 were investigated. Maximum pellet axial dimensions and maximum pellet sphericity percentage were obtained when a ratio of 20:1 was applied. The lowest adhesive material concentration (5 %) showed a distinguished pellet size, volume and weight when compared to higher concentration. On the other hand, small quantity of 50 mm 3 adhesive solution per 500 g pelleting material gave maximum pellet volume and weight, however, the maximum quantity of (150 mm 3 / 500 g pelleting material) gave the greatest sphericity percentage of 76.33%. Ratio of pelleting material components (pentonite / lime) showed that a ratio of 75% Pentonite: 25% lime gave maximum pellet dimensions, volume and weight, while a ratio of 0% Pentonite: 100% lime showed maximum sphericity percentage. Maximum contact stress and cutting strength decreased with increasing the geometric diameter of the pelleted seeds for all investigated parameters. Both germination and vigor percentages of pelleted seeds were decreased when compared with untreated seeds. Meanwhile, germination rate of pelleted seeds increased when compared with untreated seeds. Therefore, germination and vigor of high quality sesame seeds did not enhanced by pelleting process, while rate of germination remarkably increased when seeds were pelleted perior planting. Pellet dimensions, volume and sphericity are the major variables had a remarkable relation with germination and vigor percentages.

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Seeds of faba bean (Vicia faba , L) cv. Giza 40 , soybean (Glycine max , L) cv. Giza 22 and chickpea (Cicer areitinum , L) cv. Giza 1 were separated manually just after physiological maturity . Collected seeds contained 6.2 , 5.5 and 5.9 % moisture content for faba bean , soybean and chick pea respectively prior to expose them to mechanical damage by a device constructed and used to induce various levels of internal injuries. Different impact stresses were selected to induce invisible mechanical damage, whereas , six forces which is the combination between three different impact stresses and two seed positions were used . Seed placed on the device either seed side face the falling weight (SFL) or embryonic axis face the falling weight (EAFL). Increasing impact stress caused seed to lose its vigourisity when faba bean, soybean and chick pea seeds stressed by F 1 , F 2 and F 3 . Seed position as well showed significant differences in all characters studied, whereas, seeds received falling load upon embryonic axis (EAFL) were more dramatically affected than seeds received falling load upon cotyledon area (SFL) of all studied legume species. Sensitivity of (EA) is not the only reason for vigourisity dramatic reduction occurred at (EAFL) position, but also the increment of figured loads from F 1 , F 2 and F 3 in (N/mm 2 ) for (SFL) position to F 1 , F 2 and F 3 in (N / mm 2 ) for (EAFL) position. Increasing contact area due to the seed shape caused figured impact stresses to be lower in faba bean seed, therefore, these lower forces enable the seed to survive the impact stress more than soybean and chick pea seeds . Not only the load used to induce internal damage affect the level of injury , but also part of seed to receive that load as well as the area that receive the load are factors to be paid more consideration when actual stresses to be figured . performance of (Fg) in diagnosing seed cracks in all studied species was the lowest , whereas , this method showed equal capability with other diagnosing method in diagnosing broken faba bean and soybean seeds. Visual, X-ray and tetrazolium had equal capability diagnosing seed cracks and broken areas of the three studied legume species. Highly negative correlation was found between broken seeds with vigour % as well as germination % of all studied legume species . Correlation analysis showed positive correlation between dead seeds % and all broken seeds of all studied legume species. Differences in diagnosing methods (visual , X-ray and Tz ) capability were narrowed showing close capability in predicting seed quality as well as in diagnosing seeds internal damage.