Element Analysis Of Cross-section Research Articles

Hot corrosion studies on fully austenitic stainless steel in air oxidation and simulated waste heat incinerator environment at 600 °C, 650 °C and 700 °C

The purpose of the current study is to compare the hot corrosion performance of SMO 254 exposed to air oxidation and molten salt with a eutectic mixture of 40 wt% Na2SO4 + 40 wt% K2SO4 + 10 wt% NaCl + 10 wt% KCl at 600 °C, 650 °C and 700 °C under cyclic conditions for 50 h period. Kinetics of corrosion were analyzed by thermogravimetric method. By using SEM/EDS, the hot corroded specimens were investigated for surface scales and cross-sectional elemental analysis by point, line mapping methods. An accelerated rate of corrosion rate was noticed in the specimen exposed to molten salt at 700 °C, and the lowest rate of corrosion rate was observed in the specimen subjected to air oxidation at 600 °C. XRD analysis is done to analyze the corrosion products in the oxide scale.

Finite element analysis of cross section of TBR tire

With the development of science and technology, finite element analysis technology has gradually become the main means of radial tire analysis. However, most of the theoretical models are mainly analyzed, and there are still some differences between them and the actual tire models. In this article, the constitutive model of Yeoh rubber material is selected for the uniaxial tensile results of various rubber materials used in the tire. The material parameters are determined by the equivalent tensile strain curve of the steel cord. Taking the 12.00R20 tire as an example, with the help of ABAQUS software, a finite element method for the analysis of the tire structure is formed under the working conditions of assembly, punching gas and loading, and the necessary evaluation of the finite element results of the loading condition is also carried out. By analyzing the stress and strain of each part of the tire, the strain ratio can be used as the basis for the further analysis of thermal fatigue, and it also plays a guiding role in improving the design of tire structure.

Mechanical and microstructural properties of carbon nanotubes reinforced chromium oxide coated boiler steel

PurposeThe purpose of this study was to fabricate carbon nanotubes (CNT)-reinforced chromium oxide coatings and investigate mechanical and microstructural properties of these newly developed coatings on the boiler tube steel.Design/methodology/approach1 and 4 Wt.% CNT-reinforced Cr2O3 composite coatings were prepared and successfully deposited on ASTM-SA213-T22 (T22) boiler tube steel substrates using high-velocity oxy fuel (HVOF) thermal spraying method. Microhardness, porosity, metallography, X-ray diffraction (XRD), scanning electron microscopy (SEM)/energy-dispersive X-ray spectroscopy, cross-sectional elemental analysis and X-ray mapping analysis have been used to examine the coated specimens.FindingsThe porosity of the CNT-Cr2O3 composite coatings was found to be decreasing with the increases in CNT content, and hardness has been found to be increasing with increase in percentage of CNT in the composite coatings. The CNT were able to increase hardness by approximately 17 per cent. It was found that the CNT were uniformly distributed throughout Cr2O3 matrix. The CNT were found to be chemically inert during the spraying process.Originality/valueIt must be mentioned here that studies related to fabrication of HVOF sprayed CNT reinforced Cr2O3 composite coatings on T22 boiler tube steel are not available in the literature. Hence, present investigation can provide valuable information related to fabrication and properties of CNT reinforced coatings on boiler steel.

Effect of crystallinity and thickness on the diffusion barrier behavior of electroless nickel deposit between Cu and solder

The crystallinity of electroless nickel deposit was manipulated by applying bath stabilizer including lead acetate and thiourea. A crystalline deposit and a higher deposition rate of electroless nickel were achieved with thiourea than with lead acetate. The effect of crystallinity on the diffusion barrier performance of the electroless nickel deposit was studied between solder and Cu deposit. The thickness of the electroless nickel deposit investigated includes 1, 3, and 5 /spl mu/m. It was found that both crystalline and amorphous deposits perform similarly in barrier performance except when the thickness of the deposit is as thin as 1 /spl mu/m. Cross sectional elemental analysis results indicate that a 3 /spl mu/m thickness deposit can withstand ten times of reflow without counter diffusion between Sn and Cu, although Ni-Sn intermetallic compounds were formed. The 3 /spl mu/m thickness is also adequate for barrier function after 1000 hours of aging at 150/spl deg/C.