A 3D nonlinear approach for predicting the fatigue damage of plain journal bearings is proposed. The criterion selected, among several models, inspired by Dang Van’s but modified through an ascending slope in tensile direction. This consistent with stresses seen on bearing shells hydrodynamic oil pressure and allows to reflect severity compressive multiaxial non-proportional loading. From a tes...

This paper presents a comparative study of the characteristic of unfoamed and foamed geopolymers after exposure to elevated temperatures (200-800 °C). Unfoamed geopolymers were produced with Class F fly ash and sodium hydroxide and liquid sodium silicate. Porous geopolymers were prepared by foaming with hydrogen peroxide. Unfoamed geopolymers possessed excellent strength of 44.2 MPa and degrade...

The objective of this paper to present the recent development in the field of gear failure analysis. By the help of this paper we can know about different types of failure detection and analyzing techniques which is used to reduce these failures from gears. The basic reasons of gear failure misalignment of gear, spalling, pitting etc, follow the reason of gear failure. which is identified from ...

To take advantage of the synergistic effects of Pt and Zr, a kind of Zr-doped, Pt-modified aluminide coating has been prepared by a hybrid process, first electroplating a Pt layer and then co-depositing Zr and Al elements by an above-the-pack process. The microstructure and isothermal oxidation behavior of the coating has been studied, using a Pt-modified aluminide coating as a reference. Resul...

Bearings are essential parts used in machine tools where high precision is required. It is important to understand bearing failure in order to replace a bearing before it affects the quality of precision. Bearing failure appears as a run-out in some applications, which is a critical factor for precision. However, previous studies have only focused on failure mechanisms, such as spalling. In thi...

Attack of Portland cement by ambient sulfates presents a considerable risk to structures in some environments. In this study, x-ray microtomography, a high resolution variant of medical “CT”, noninvasively mapped the progression of damage in Portland cement resulting from exposure to an aqueous solution of Na2SO4 (sodium ion concentration of 10,000 ppm). Cement paste samples from water-to-cemen...