Abstract Rotary Friction welding is one of the most popular methods of joining similar and dissimilar materials. It is widely used with metals and thermoplastics in a wide variety of aviation, transport and aerospace industrial component designs. This study investigates the influence of friction and upsetting pressures on the hardness, tensile properties and microstructure of the welds. The experimental results showed that as the friction and upsetting pressures increased, the hardness and tensile strength values increased, as well. The tensile fracture of welded joint occurred in the AISI 1060 side. The friction processed joints were evaluated for their integrity and quality aspects by optical and scanning electron microscopy. For the perfect interfacial bonding, sufficient upsetting and friction pressures are necessary to reach the optimal temperature and severe plastic deformation to bring these materials within the attraction range.
Fatty acids are very important biological substances due to their metabolic, structural and signal- ing functions. Omega-3 has different beneficial, harmful and neutral effects on adipokines. Adi- pokines have autocrine, paracrine and endocrine effects on metabolism. In the study 54 German Fawn x Hair crossbred goats were synchronized using intravaginal sponges. During the first pe- riod (mating-75 days), all animals were fed a diet supplemented with protected fat and during the second period of pregnancy (76 days-kidding), one of the groups was fed a diet supplemented with fish oil and other was fed a diet supplemented with protected fat. Serum leptin, ghrelin, adi- ponektin and omentin levels were measured by ELISA system. Distributed fed (roughage and concentrate) were sampled and dry matter, crude protein, fat, and ash were determined by AOAC (1988) analysis methods. The Acid Detergent Fiber (ADF) and Neutral Detergent Fiber (NDF) analysis were conducted using heat stable α-amylase and sodium sulphite. Fat source (fish oil or protected fat) affected feed consumption and the highest feed consumption was found in the group fed with protected oil first half of the pregnancy and with fish oil in the second half of the pregnancy and in the fish oil group during the pregnancy. It was determined that the use of fish oil during pregnancy did not affect ghrelin, leptin and omentin concentrations in serum. Adipokine levels of fish oil fed animals during any period of pregnancy were found to be high and it was also found that serum adiponectin levels in goats fed with diet containing fish oil in the first half of pregnancy and protected fat in the second half were statistically significantly high in adipokines.