The Effect of Long-Term Ageing on the Degradation of the Microstructure the Inconel 740h Alloy

Abstract

The Inconel 740H alloy is used in the construction of pressure components of ultra-supercritical operating parameters. The paper presents the results of microstructure analysis after 1000 and 10 000 h ageing at 700 and 750 • C. Microstructure studies were made using scanning and transmission electron microscopy. Identification of precipitations was made using X-ray analysis of phase composition. The influence of ageing time on changes in microstructure and the precipitation process of the tested alloy were described. Presented research results are a material characteristic of new generation materials, which are used in the design of elements of pressure parts of boilers and diagnostics work during operation.

An Analysis of Creep Phenomena in the Power Boiler Superheaters

“…The constants in Equation 15are calculated based on the results of uniaxial creep tests conducted in Institute for Ferrous Metallurgy (IMŻ) [16][17][18][19]. In order to find initial values for all coefficients in Equation (15) before the final multivariate approximation is carried out, the algorithm described below is applied.…”

Introductory Chapter: Creep - An Overview of New Research Results

“…The service within the time as assumed by designers as well as the extension of the lifetime of the materials and products made from them which have worked the design service life are most often determined by the calculation method based on creep strength data and positive results of comprehensive mechanical tests [7][8][9][10][11]. Among materials, the products operating under creep conditions are of particular importance.…”

Magnesium–lithium alloys with TiB and Sr additions

“…Looking for new materials that meet the requirements of modern constructions, minimising mass while maintaining high properties and even increasing durability lead to the development and testing of magnesium alloys belonging to the group of light alloys [1][2][3].…”

“…Magnesium alloys give the potential for mass and associated energy savings in both the automotive and aerospace applications as all possess the highest strength-to-mass ratio to basic structural alloys. Despite the expensive cost, this potential advantage has led to a recent rise in interest on the cast and wrought magnesium components [2][3][4].…”