-The steady-state creep deformation behavior of a cast two phase gamma TiA1 alloy having the composition Ti-48AI 1Nb (a t . ° ) has been studied. Tension creep tests using the stress increment technique (a~ < cr 2 < or3) were conducted over the temperature range of 704-850°C at constant initial applied stress level of 103.4-241.3 MPa. The activation energy for creep over the temperature and str...

In superalloys, topologically close–packed (TCP) phases, which contain refractory elements, usually significantly influence the mechanical properties. The current work investigates structure and composition of TCP phase in an Al–Mo–rich Ni–based single crystal superalloy. It is shown that after 40 h thermal exposure, a large number strip–like phases are formed, enriched Mo Re. identified as tet...

In the Present study, attempt will be made to propose a new method for prediction of long-term essential creep of concrete utilizing some short-term creep tests under high temperature. To do so, regarding the similarities between essential creep of concrete and creep in viscoelastic materials, the time–temperature equivalence relation in viscoelastic materials is evaluated for concrete. This re...

Titanium alloys have great potential as candidate materials for the deep-sea facilities. Long-term creep deformation behavior of pressure-bearing structures made titanium under alternating compressive stress has a direct impact on structural stability. The evaluations Ti-6Al-4V ELI with basketweave microstructure stresses been carried out by uniaxial tester. deformations strong sensitivity due ...

The effects of the modification a high-?' Ni-8.5Cr-5.5Al-1Ti (wt.%) model superalloy with 0.5 wt.% Y2O3, manufactured by laser powder-bed fusion, on microstructure and compressive creep resistance were investigated. Compared to base alloy, oxide-dispersion strengthened (ODS) alloy exhibits 8-10 times slower rates at 800 °C, over wide range stresses (35-250 MPa). Two regimes observed: diffusiona...

The creep deformation of 3rd generation 2xxx Al-Li alloys in age forming (CAF) is unsatisfactorily low due to its high strength and required ageing temperature, especially for the commonly used T8 temper. Promoting such process will significantly reduce springback CAF, making easier compensation tool design. In this study, two possible routes inducing increased were explored, one by employing a...

Peridotites of Ulten Zone (Eastern Alps, N Italy) show a transition from coarse protogranular spinel lherzolites to fine-grained amphibole + garnet peridotites, recorded by the crystallization coronas around spinel. Pyroxenite veins, transposed along peridotite foliation, similar metamorphic evolution coarse-grained (garnet-free) websterites websterites. In both peridotites and websterites, pre...

Abstract Single crystal Nickel-based superalloys exhibit an anomalous yield point, the stress increasing with temperature to a maximum at around 750 ºC. Here, we demonstrate in alloy CMSX-4 ºC that, although there is virtually no effect of strain rate on initial slow rates second mechanism can initiate leading considerable softening effect. By examining microstructures series interrupted tests,...

Abstract. Viscous flow in ice is often described by the Glen law – a non-Newtonian, power-law relationship between stress and strain rate with exponent n ? 3. The attributed to grain-size-insensitive dislocation creep; however, laboratory field studies demonstrate that deformation can be strongly dependent on grain size. This has led hypothesis at sufficiently low stresses, controlled boundary ...