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High-temperature dissimilar connections built of Inconel 718 and AISI 410 martensitic stainless steel (MSS) are widely used in a range of industries, including boiler construction, the chemical industry, aerospace, and nuclear. When compared to other materials, Inconel 718 and AISI 410 martensitic stainless steel offer superior strength and corrosion resistance under a variety of environmental conditions. The rotational speed was adjusted between 1100 and 1500 RPM, while the friction pressure, friction time, forging pressure, and forging duration were all kept constant during the testing. Five sets of testing were performed, with the resultant tensile strength (both room temperature and hot tensile) and Vickers Hardness being recorded for each set of trials. To assess the structural integrity of the joints, a detailed microstructural investigation, SEM-EDS, and XRD were performed at their interfaces. Mechanical properties were revealed to be high at 1300 RPM due to the small grain size at the interface region; ultimate tensile strength and hardness were determined to be 571 MPa and 423 HV, respectively, due to the small grain size at the interface region. Additionally, a pitting corrosion study has been conducted on dissimilar welded joints at optimum conditions, and their results were discussed and compared with base metals.

Laser hardfacing were produced using a high power Disk laser of 4 kW maximum power as a heat source to melt and bond the Colmonoy-5 powder on to AISI 316 LN stainless steel substrate. Significant difference in melting points between the austenitic stainless steel (ASS) substrate and Ni-based Colmonoy alloy results in substantial dilution of the hardfaced deposit from the substrate. In this present study, the effect of travel speed (TS) on microstructure, microhardness and wear characteristics laser hardfaced deposits were investigated. The phase constitution, microstructure and hardness of laser hardfaced deposits were examined by optical microscope, scanning electron microscope, energy dispersion spectroscopy, x-ray diffraction and Vickers hardness tester. The TS was varied between 300 and 500 mm/min. The other parameters such as, laser power, powder feed rate, and defocusing distance were kept constant. From this investigation, it is found that the deposit hardness increased from 750 HV to 800 HV with decreasing in TS. The TS increases, bead height decreased and dilution and depth of penetration increased. Due to higher TS the faster cooling rate takes place, it causes the cracking and porosity. Microhardness and wear resistance are slightly improved in the TS of 400 mm/min. The microstructures of deposit layer are composed of Ni-rich carbide, boride and silicide, this are the responsible for higher hardness and better wear resistance.

In this investigation, an attempt has been made to optimize the laser hardfacing (LH) parameters such as power, powder feed rate (PFR), travel speed and defocusing distance to maximize hardness of Ni-based hardfacing surfaces. Statistical tools such as the design of experiments (DoE), analysis of variance (ANOVA) are used to develop the empirical relationship to predict the hardness of the deposits at the 95% confidence level. Response graphs and contour plots are constructed using response surface methodology (RSM) concept. From this investigation, it is found that the maximum hardness of 820.48 HV could be achieved for the deposit made using a power of 1314 W, PFR of 9 g/min, a travel speed of 366 mm/min, and a defocusing distance of 32 mm.

Cement-based materials are increasingly and widely employed in infrastructure development; however, they pollute our environment by generating carbon dioxide, which is detrimental to our civilization. In self-cleaning concrete, photocatalysts accelerate the decomposition of organic particles; thus, photocatalytic degradation of gaseous pollutants could reduce pollution. The incorporation of photocatalytic components enhanced the mechanical self-cleaning properties of cement mortar. In this study, 4–6 percent by weight of rutile TiO2 was added to mortar, and the results were compared to those of a control sample. On the proposed mortar cubes, both fresh mortar and hardening mortar experiments were conducted. Because the initial and final setting times of TiO2 differ from those of conventional cement mortar, the surplus TiO2water-cement ratio had to be modified. The adaptability of the sol-gel method enables the use of various process parameters to influence the properties of the produced TiO2 nanoparticles. The compressive strength was calculated for 7, 14, 21, and 28 days, and an ultrasonic velocity test was performed after 28 days. On mortar samples, acid and sulfate attack experiments were performed. The M-3 mortar mixture containing 5% rutile exhibited the highest level of strength compared to the other mixtures. The M-3 exhibits a strength that is 10.96% greater than that of the control mix. The impact of acid and sulfate attack on the strength of mix M-2 is relatively modest in comparison to other mixtures. Using RhB (rhodamine color) discoloration under UV light, such as sunlight, the photocatalytic mortar is concentrated; a typical test for self-cleaning cementitious materials reveals the presence of more photocatalytic material, which yields the best results. [ABSTRACT FROM AUTHOR]

Forty sesame (Sesamum indicum L.) involving eight high yielding popular varieties and five sesameshoot webber resistant genotypes were evaluated to study gene action, combining ability and heterosis.Among the parents, the lines VS 9701, CO 1, SVPR 1 and Rama and the testers Si 3315/11 and ES 22were the best for most of the yield and yield contributing characters (including shoot webber resistance)based on mean performance and gca effects. Considering the mean performance, sca and standardheterosis, five hybrids viz., VS 9701 × Si 3315/11, CO 1 × Si 3315/11, SVPR 1 × ES 22, VS 9701 × ES22 and Rama × Si 3315/11 were found to be superior for seed yield and shoot webber resistance andrecommended for further evaluation.

2xxx and 7xxx high strength alloy are well suited for components and structures that include a greater strength ratio and are typically used in the fabrication of fuselage, wing skins. AA2014 is hard to join using a fusion welding process because of its good thermal conductivity, oxidation behaviour and low fusion point, which can easily lead to burn through and porosity. To overcome the above difficulty, friction stir welding (FSW) is used. The formation of sound weld depends on process and tool parameters. The tool shoulder is the most predominant factor. About two-third of heat is generated at the interface of tool and sheet. Hence, in this investigation, the influence of the tool shoulder diameter (D) to sheet thickness (T) ratio on the tensile properties of FSW AA2014 joints was analysed. Five tools with varying D/T ratios (2.0, 2.5, 3.0, 3.5 and 4.0) were used. Microstructure and hardness measurement were performed to correlate strength properties of FSW joints. It is found that the joint welded with a D/T ratio of 3.0 disclosed superior joint tensile properties compared to other D/T ratios. It is mainly due to the development of fine-grained structure in stir zone of D/T 3.0 joints. [ABSTRACT FROM AUTHOR]

Laser hardfacing is a method whereby another layer of material is deposited onto a substrate by laser fusion of blown powders or pre-placed powder deposit. Multiple layers can be saved to form shapes with complex geometry. This manufacturing procedure has been utilized for modifying the material surface property and for the repair of the component. There are many parameters which have influence on controlling the characteristics of laser hardfaced surfaces and one such parameter is powder feed rate. In this investigation the effect of powder feed rate on microstructure, microhardness and wear resistance of laser hardfacing Ni-based Colmonoy-5 alloy (Ni-Cr-Si-B-C) powder onto a 316LN austenitic stainless steel substrate was analysed. The powder feed rate was varied from 3 to 11 g/min. The other parameters such as laser power, travel speed and defocusing distance were kept constant. From this investigation, it was found that the deposit hardness increased from 500 to 800 HV with increase in powder feed rate. The microstructure of the hardfaced deposit primarily consists of the γ-Ni phase and the interdendritic eutectic mixture comprises γ-nickel, nickel-rich borides and chromium-rich carbides. These contribute to higher hardness in deposits at higher powder feed rate. [ABSTRACT FROM AUTHOR]

In formal language theory, we are mainly interested in the natural language computational aspects of ω-languages. Therefore in this respect it is convenient to consider fuzzy ω-languages. In this paper, we introduce two subclasses of fuzzy regular ω-languages called fuzzy n-local ω-languages and Büchi fuzzy n-local ω-languages, and give some closure properties for those subclasses. We define a deterministic fuzzy automaton acceptance conditions on fuzzy ω-languages and fuzzy n-local automaton. The relationship between deterministic fuzzy n-local automaton and two subclasses of fuzzy regular ω-languages are established and proved that every fuzzy ω-language accepted by a deterministic fuzzy automaton in 2-mode is a projection of a Büchi fuzzy 2-local ω-language. [ABSTRACT FROM AUTHOR]