1967 Price 8s 6d net .-summary The time hardening, life fraction and strain hardening hypotheses variously proposed to describe tiniaxisl creep deformation are considered and compared with experimental evidence. It is concluded that the strain hardening hypothesis is the most nearly correct, the experimental strains usually being within 50% of those predicted. Further, rheological and modified ...

This paper presents the application of a life fraction hardening rule to the analytical calculation of creep in hot section components. Accurate prediction of creep is critical to assuring the mechanical integrity of heavy-duty, industrial gas turbine (IGT) hardware. The accuracy of such predictions depend upon both the creep models assumed and how those models are implemented in a finite eleme...

The process of laser beam transformation hardening is principally controlled by two independent parameters, the absorbed laser power on a given area and the interaction time. These parameters can be transformed into two functional parameters: the maximum surface temperature and the hardening depth. It has been proved that with a constant hardening depth the results (hardness. residual stress. e...

The effect of post-irradiation annealing on the microstructures and mechanical properties of V-4Cr-4Ti alloys was studied. Helium-hydrogen-irradiated sequentially V-4Cr-4Ti alloys at room temperature (RT) were undergone post-irradiation annealing at 450 °C over periods of up to 30 h. These samples were carried out by high-resolution transmission electron microscopy (HRTEM) observation and nanoi...

Case hardening is a feature of dried wood that causes the wood to deform (cup) after re-sawing and equalising the moisture content. VTT has analysed case hardening with the aid of the simulation model PEO and with experimental drying, conditioning and storage tests. Case hardening cannot be predicted by the moisture content gradient alone. However, the case hardening gap after drying to a high ...

Precipitation hardening, because it involves the hardening of the material over a prolonged time, is also called age hardening, or ageing. By the appropriate heat treatment of precipitation hardening, the strength or hardness of some heat-treatable aluminium alloys can be enhanced by the formation of nano-meter sized second-phase precipitated particles within the original phase matrix. The fine...

The boundary value problem representing one time step of the primal formulation of elastoplasticity with positive hardening leads to a variational inequality of the second kind with some non-differentiable functional. This paper establishes an adaptive finite element algorithm for the solution of this variational inequality that yields the energy reduction and, up to higher order terms, the R−l...

We propose a modified Invasion Percolation (IP) model to simulate the infiltration of glue into a porous medium under gravity in 2D. Initially, the medium is saturated 15 with air and then invaded by a fluid that has a hardening effect taking place from the interface towards the interior by contact with the air. To take into account that interfacial 17 hardening, we use an IP model where capill...