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A novel quaternary medium-entropy rock-salt oxide (Mg 0.25 Co 0.25 Ni 0.25 Zn 0.25)O (MERO) was predicted using first-principles calculation and prepared through solid-state reaction. The first-principles study demonstrated that the mixing enthalpy and entropy values of the MERO are 2.377 kJ/mol and 0.693–1.040 R, respectively. The single-phase MERO can be obtained from 1000 °C to 1200 °C, demonstrating good thermal stability, whereas a completely disordered occupancy of different metal cations can be confirmed by Raman spectroscopy. The Transition Electron Microscope (TEM) analysis reveals that the MERO exhibits an FCC structure with a lattice parameter of 4.384 Å. The dielectric permittivity ε r of MERO prepared at 1200 °C shows relatively high values of 6.4 × 103 and 18.40 corresponding to frequencies of 100 Hz and 1 MHz at room temperature, exhibiting a potential for application in electrode materials and capacitors. [ABSTRACT FROM AUTHOR]

Silica-based ceramic cores are extensively used to form the complex hollow structure inside turbine blade. However, the excellent mechanical properties and high dimensional accuracy of ceramic cores are very crucial to obtain the hollow turbine blade with high precision, which is still a challenging work. In this study, silica-based ceramic cores with silicon nitride addition were prepared for improving the mechanical properties and dimensional accuracy. Results showed that the linear shrinkage of silica-based ceramic cores significantly decreased from 1.21 % to 0.087 % and the porosity gradually increased from 17.9 % to 22.1 % with the increase of Si 3 N 4 content. The weight gain of cristobalite in the core samples after sintering first increased and then decreased, where the sample with 5 wt% Si 3 N 4 had the maximum cristobalite content of 4.4 wt%. The appropriate Si 3 N 4 content (5 wt%) in the silica-based ceramic cores could enhance the flexural strength at room temperature to 16.84 MPa by promoting densification process. However, the excess Si 3 N 4 content (more than 10 wt%) could hinder the densification process and enlarge their porosity, decreasing the flexural strength at room temperature. Meanwhile, the high temperature strength at 1500 °C was decreased owing to the increasing porosity caused by the re-oxidation of Si 3 N 4 particles. Therefore, it was concluded that the silica-based ceramic cores with 5 wt% Si 3 N 4 showed higher mechanical properties and lower linear shrinkage, which offered a way to maintain the excellent mechanical properties and high dimensional accuracy of ceramic cores. [ABSTRACT FROM AUTHOR]

• Investigated the influence of sliver defects on the creep rupture life of nickel-based single crystal superalloys. • Revealed the damage mechanism of sliver defects on the creep life of single crystal superalloys through SEM and EBSD observations. • Developed creep constitutive equations for specimens containing sliver based on crystal plasticity theory, explaining the reasons for the decrease in sample life caused by sliver. • Predicted the damage tolerance of sliver defects with different orientations. Sliver defects are common casting imperfections in the preparation of single crystal blades, significantly impacting the high-temperature mechanical performance of blades and potentially leading to blade failure. A detailed study was conducted on the microstructure of sliver in the second-generation nickel-based single crystal superalloy CMSX-4, focusing on its influence on creep performance at 980 °C/250 MPa. Results indicate a substantial impact of sliver on the creep performance of single crystal superalloys, with a 26.37 % reduction in creep rupture time for samples with sliver compared to those without. Fracture analysis reveals that sliver primarily contributes to performance deterioration by promoting the extension of grain boundary microcracks through grain boundary sliding during the creep process, accelerating sample fracture. Utilizing crystal plasticity theory, a successful fit was achieved for the creep rupture life of samples with sliver, allowing the prediction of fracture life for samples with different orientations of slivers. Predictive results suggest that, for CMSX-4 alloy, the orientation of the sliver should be restricted to within 8°. [ABSTRACT FROM AUTHOR]

• Climate change, hydrological and hydraulic model are combined to analyze runoffs. • Four Global Climate Model: BCC, BNU, CanESM and CSIRO are used. • The future design runoffs and water levels increase in Qu River. • Disaster management and infrastructure construction should be paid more attention to. The impact of climate change on regional hydrological extreme events has been a research topic that has received much attention in recent years. This paper aims to provide a general overview of changes on future runoffs and water levels in the Qu River Basin, upper reaches of Qiantang River, East China by combining future climate scenarios, hydrological model and 1D hydraulic model. The LARS-WG (Long Ashton Research Station Weather Generator) statistical downscaling method is used to downscale the GCM (Global Climate Model) outputs (including BCC, BNU, CanESM and CSIRO under RCP4.5 and RCP8.5 scenarios) and generate 50 years of synthetic precipitation and maximum and minimum temperatures to drive the GR4J hydrological model and the 1D hydraulic model for the baseline period 1971–2000 and the future period 2021–2050. Finally, the POT (Peaks over Threshold) method is applied to analyze the change of extreme events in the study area. The results show that design runoffs and water levels all indicate an increasing trend in the future period for Changshangang River and Jiangshangang River at most cases, especially for small return periods, and for Qu River the increase becomes larger, which suggests that the risk of flooding will probably become greater and appropriate adaptation measures need to be taken. [ABSTRACT FROM AUTHOR]

The microstructure evolution and room temperature fracture toughness of directionally solidified NiAl–31Cr3Mo–0.2Si (at%) near-eutectic alloy at different withdrawal rates were investigated. The results showed that NiAl dendrites were eliminated and fully eutectic structure was achieved by applying appropriate withdrawal rates. The microstructure evolved from planar eutectic to primary NiAl dendrites + cellular eutectic and then to dendritic eutectic with the increasing withdrawal rate. Correspondingly, the interlamellar spacing and cell size decreased gradually. The relationship between eutectic interlamellar spacing with withdrawal rate can be summarized as λ = 4.74 V − 0.38 . The fracture toughness of alloys with fully eutectic structure was much higher than that of alloys with NiAl dendrites. It increased up to 2.5 times. The high fracture toughness may be attributed to some toughening mechanisms, such as crack bridging, crack deflection, interface debonding and microcrack linkage. The existence of primary dendrites would seriously deteriorate the fracture toughness. [ABSTRACT FROM AUTHOR]

The Si 3 N 4 ceramic was joined to DZ483 superalloy by partial transient liquid phase bonding using Ti/Au/Ni/Ti multi-interlayers. The interfacial microstructure and crystallographic orientations between the Si 3 N 4 ceramic and the Ni interlayer were analyzed by scanning and transmission electron microscope. The results indicated that the interfacial microstructure of the joint consists of three main phases: a TiN reaction phase, an Au-rich phase, and a lamellar Ni-rich phase distributed homogenously in the Au-rich phase. The nano-scale wavy interface was observed at the Si 3 N 4 /TiN interface, which was thought to provide high mechanical strength. A possible mechanism for the formation of interfacial structure observed was discussed. [ABSTRACT FROM AUTHOR]

The effect of a high magnetic field on the dendrite morphology of superalloy DZ417G during directional solidification at a low solidification velocity has been investigated experimentally. It was found that the magnetic field induces columnar to equiaxed transition (CET) and makes the primary dendrite arm spacing decrease. In addition, the magnetic field causes deformation of the solid–liquid interface shape and the macrosegregation in the mushy zone. Based on these results, it was found that both of the thermoelectric magnetic convection (TEMC) and the thermoelectric magnetic force (TEMF) cause CET, the change of solid–liquid interface shape and the formation of macrosegregation. This is in good agreement with predicted values of the TEMC and TEMF, respectively. The primary dendrite arm spacing was changed by the interdendritic TEMC in the magnetic field. [ABSTRACT FROM AUTHOR]

As the artificial floating bed (AFB) is more extensively applied in water treatment, the hydraulic characteristics of the AFB has been broadly investigated. However, the conventional studies on the hydraulic characteristics exhibited by the AFB tends to rigid vegetation roots, whereas the research on flexible vegetation roots is relatively less. In this study, three different characteristics of the flexible vegetation root on the AFB experiment were conducted in different hydraulic conditions to study the effect of flexible root system on the hydraulic characteristics. At the same time, the formula of drag force coefficient is obtained by combining theoretical analysis and machine learning. The main results are as follows: (1) The more fibrous roots in same root area station on the AFB, the smaller the root resistance of the AFB; (2) The drag force coefficient C Dx of flexible vegetation roots decreases with the increase of R eh ; (3) The best root coefficient for describing root characteristics is characteristic diameter d 50. [ABSTRACT FROM AUTHOR]

The extensive utilisation of zeolite catalysts in contemporary industries has resulted in the generation of considerable quantities of zeolite waste. The recycling of zeolite wastes for the preparation of highly crystalline mullite whiskers remains a significant research challenge. Mullite whiskers are often employed as enhancing the mechanical properties of ceramic matrix composites. In this study, we successfully synthesized mullite whiskers under the catalytic condition of 650 °C, utilising zeolite waste as the reaction source and MoO 3 as the liquid-phase catalyst. The XRD and SEM results indicate that the phase transition direction of the zeolite waste is influenced by the MoO 3 content and the sintering temperature. The powder mixture (M8-800), containing 8 wt% MoO 3 and subjected to a sintering temperature of 800 °C, exhibited the highest aspect ratio (22.89 ± 2.31). The synthesis of mullite whiskers via a low-temperature liquid-phase reaction mechanism is demonstrated by TEM experiments. The precursor droplets, comprising the catalyst and glass melt, serve as the initial material for whisker growth. This study proposes a novel and feasible solution for industrial waste recycling. • Exploring the phase transition between zeolite waste, Lazurite 1C, Albite low and mullite. • The interfacial engineering of the glass layer/mullite is discussed, and mullite follows a liquid-solid growth mechanism. • Exploring the industrial prospects for the preparation of mullite whiskers from zeolite wastes. [ABSTRACT FROM AUTHOR]

• The interface reaction of superalloy CMSX-4 and ceramic core is carried out during directional solidification. • A continuously distributed Al 2 O 3 layer is formed at superalloy/silicon oxide ceramic core interface. • A discontinuously distributed Ta/Ti enrichment carbide ((Ta/Ti)C) layer is formed at Al 2 O 3 layer/superalloy interface. • The formation mechanism of the interface reaction is analyzed. To clarify and comprehend the interfacial compatibility of single crystal superalloy and ceramic core, the interface reaction of nickel-based single crystal superalloy CMSX-4 and silicon oxide ceramic core during directional solidification is investigated. The results revealed that a continuously distributed Al 2 O 3 layer is formed at the interface of superalloy / silicon oxide ceramic core. Moreover, it is also found that a discontinuously distributed Ta/Ti enrichment carbide layer, (Ta/Ti)C, is formed at the interface of Al 2 O 3 layer/superalloy. The formation mechanism of interface reaction between the nickel-based single crystal superalloy and silicon oxide ceramic core is analyzed. [ABSTRACT FROM AUTHOR]

Chemical distributions, local phase and domain configurations of xBiFeO 3 -(1-x)BaTiO 3 (BF-BT) ceramics with different macroscopic phases were carefully studied to understand the structural mechanisms of electric properties. Universal BF-rich@BT-rich@average-composition triple core-rim structures were found to exist in all the compositions, and the volume fractions of cores decrease with the BF content. The inner cores all show dominant rhombohedral (R) phase, while the rims change from dominant pseudo-cubic (PC) phase with polymorphic polar nanoregions (PNRs) (x = 0.64) to coexistence of R and PC with PNRs and nanodomain (x = 0.7) and then to dominant R phase with PNRs+macrodomain (x = 0.75). The high densities of phase and domain boundaries are responsible for the high and thermal-stable electric-field induced strain in the PC phase. Our results evidence the decisive contribution of the composition-modulated hierarchical microstructures to the electric-field induced strain, and are anticipated to provide the necessary foundation for the effective modulation of the piezoelectricity. [ABSTRACT FROM AUTHOR]

The effects of surface modification of the La–Mg–Ni based alloys through doping a trace of Y 2 O 3 on the electrochemical properties are researched in this study. The electrochemical hydrogen storage capacities and cycle stabilities of the Y 2 O 3 @La 1.7 Mg 1.3 Ni 9 samples are all significantly improved and the performance reaches the best for the 10 h milled sample. Comparing to the previous data, the comprehensive performances have already surpassed the most alloys, especially in the cyclic stability properties. The Y 2 O 3 coating layer with the amorphous structures will be formed on the alloys surface during the milling process, which has a certain capability of electricity catalysis to further improve the electrochemical hydrogen storage properties. Meanwhile, the results also indicate that much longer milled duration is harmful to the electrons transfer process, and the point is further confirmed through XPS analyses. • Trace Y 2 O 3 is applied to the hydrogen storage alloy surface modification. • Structure transition is investigated during the milled process. • The C max and S 30 can reach above 390mAh/g and 90%. • The main hydrogen storage properties have surpassed the most alloys. [ABSTRACT FROM AUTHOR]

Nano-Ni drived modification in LaMg 3 /Ni composite is investigated. The new phases of LaMg 2 and MgNi 2 can be formed on the sample surface during the milling process. There is almost no electric charge transfer process between Ni and La element through XPS analyses. The amorphization structure can be found on the alloy surface with the increasing of reaction duration, and the capacity and cycle stability are also greatly promoted. On the other hand, the milled alloys show the lower charge transfer resistance, better anti-corrosion ability and higher oxidation current density. [ABSTRACT FROM AUTHOR]

The silica-based ceramic core is an essential part of the investment casting of hollow turbine blades due to their excellent thermal stability and easy demoulding. In this study, the green bodies of silica-based ceramic cores with nano-ZrO 2 were fabricated by stereolithography (SLA). Firstly, the effects of the burying process and debinding heating rates on the performance and microstructure of silica-based cores were investigated. The results revealed that the burying powders provide support and a stable thermal field for the SLA ceramic cores during debinding and sintering. Ceramic cores with smaller shrinkage and higher apparent porosity were produced during the burying process at a heating rate of 0.5 °C/min. In addition, the influence of nano-ZrO 2 content on the mechanical properties of silica-based ceramics was investigated. Nano-ZrO 2 particles can improve bulk density and mechanical properties by promoting sintering. Additionally, it can reduce the cracks on the surface of ceramic samples. The optimal content of nano-ZrO 2 should be between 1.5 and 2 wt%, producing silica-based cores with low shrinkage rate (2.91–3.19%), high apparent porosity (27.11–27.97%) and high flexural strength at room temperature (24.51–24.65 MPa) and high temperature (27.81–29.69 MPa). This work provides promising ways to fabricate high-quality ceramic cores for turbine blade application. [Display omitted] [ABSTRACT FROM AUTHOR]

Laser-directed energy deposition (L-DED) is considered as an effective repair method for damaged single-crystal (SX) superalloy turbine blades. However, controlling stray grains (SGs) and epitaxial growth is still the major problem. This study investigated the influences of pre-solution treatment and intrinsic heat treatment (IHT) on the formation of SGs and epitaxial growth of L-DED René N5 SX superalloy. The γ/γ' eutectics and coarse γ' precipitates at the inter-dendrite region can be eliminated after pre-solution treatment procedures before the L-DED experiment. A lower temperature in pre-solution treatment resulted in the retention of residual γ/γ' eutectics and coarse γ' precipitates. Thus, the aggravated element segregation within the local melt pool and interface collapse during the L-DED process can result in stray grains (SGs) formation. Improved pre-solution treatment procedures can also help reduce SGs caused by the carbides in the substrate. Besides, the SG formation in the deposited layers can be attributed to the recrystallization as a result of high thermal stress during the IHT in thermal cycles. The optimized pre-solution treatment procedure reduced the elemental segregation of the substrates , resulting in a larger primary dendrite arm spacing (PDAS) from the bottom of the deposited layers. Due to IHT during thermal cycles in the deposited layers, the equivalent heat treatment process promoted the re-precipitation and growth of γ' phase. Meanwhile, the optimized pre-solution treatment procedure decreased the size of the heat-affected zone (HAZ) caused by thermal cycles. In summary, by optimizing the substrates' pre-solution treatment procedures to eliminate the γ/γ' eutectics ,coarse precipitaes and decrease the carbides in the subsrtates, the formation of SGs resulting from substrate segregation and heterogeneous microstructure can be controlled. This work provides the potential guidance of substrate pre-treatment for L-DED repair of SX superalloys. [Display omitted] • Pre-solution heat treatment procedure is benefit to the control of stray grains (SGs) in the bottom of the molten pool. • SGs found in the deposited zone were strongly associated with recrystallization. • Improper pre-solution treatment procedure increased the length of heat-affect zone (HAZ). • Intrinsic heat-treatment (IHT) caused by thermal cycles led to different microstructure evolution of γ' precipitates in the sample. [ABSTRACT FROM AUTHOR]

A relatively simple, but very effective method via magnetron sputtering process was used in the surface doping of the electrode plates. Molybdenum nano-particles coated electrodes were studied in the paper. The flower-like deposits appeared on the electrode plate surface, and Ni 4 Mo could be in-situ formed with the coating process. The hydrogen ab/desorption rates were accelerated at the beginning and dropped subsequently. The max discharge capacity and retention rate after twenty cycles of the St 5min sample reached about 370mAh/g and 92%, respectively. Comparing to the typical hydrogen storage alloys, they were much closed to the A 2 B 7 -type and have surpassed the most AB 3 -type Co-containing alloys. The activation energies and enthalpies of the various electrodes during the ab/dehydrogenation process were also discussed in details. Image 1 • Nano-Mo based coatings were used as surface modification for H 2 storage alloy. • Electrode surface transitions during the coating process were discussed. • C max and S 20 surpassed the most AB 5 -type alloys, and closed to the A 2 B 7 -type. • Properties improvements were related to the newer formed Ni 4 Mo compounds. [ABSTRACT FROM AUTHOR]

Satellite and reanalysis precipitation products, as new and complementary data sources, are attractive for hydro-meteorological applications, especially in data-sparse areas. This study evaluates the accuracy of two satellite precipitation products (TMPA 3B42V7 and PERSIANN-CDR) and one reanalysis precipitation product (NCEP-CFSR) against gauge precipitation observations with four statistical indices over the upstream of the Lancang River Basin (ULRB), Southwest China. The reliability and applicability of these precipitation products as inputs to a hydrological model (Soil and Water Assessment Tool, SWAT) for streamflow and sediment simulations are also assessed. Furthermore, we compare the spatial plots of extreme water yield (99 percentiles) and suspended sediment yield (99 percentiles) driven by the four precipitation sources, and investigate the spatial and temporal variability of water yield and suspended sediment yield over the ULRB. Results show that for direct comparisons with gauge precipitation observations, monthly TMPA 3B42V7 precipitation product performs the best at the basin scale with the smallest error and bias, and the highest correlation, followed by NCEP-CFSR, and PERSIANN-CDR. For modeling-based indirect inference, TMPA 3B42V7 presents great capability for streamflow and sediment simulations in the SWAT model on a monthly time step at the basin outlet, and PERSIANN-CDR also performs well. NCEP-CFSR shows acceptable skills in modeling sediment but unacceptable skills in modeling streamflow. Extreme water yield presents moderate spatial variability over the ULRB while extreme suspended sediment yield presents strong spatial variability. Water yield of this basin shows a decreasing trend during 1998–2008 while there is no obvious trend in suspended sediment yield in this period. Unlabelled Image • The reliability and applicability of three precipitation products are explored. • TMPA 3B42V7 is the best for streamflow and sediment modeling on monthly scale. • Extreme water/suspended sediment yield presents moderate/strong spatial variability • A decreasing/No trend is found for water/sediment yield in the basin during 1998–2008. [ABSTRACT FROM AUTHOR]

A series of 30 wt%Ni/Ce x Zr 1− x O 2 catalysts doped with Ru ranging from 0 to 5 wt% were prepared by one-pot hydrolysis of metal nitrates with ammonium carbonate for carbon dioxide methanation at low temperature range of 150–310 °C. The influences of Ce/Zr molar ratios and Ru contents on the physicochemical properties and catalytic activities of prepared catalysts were systematically investigated. The addition Ru can improve the Ni dispersion and the basicity of the y Ru-30Ni/Ce 0.9 Zr 0.1 O 2 catalysts surface. As a result, their low-temperature catalytic activity had been enhanced over these doped Ru promoted catalysts. The optimal catalyst was 3Ru-30Ni/Ce 0.9 Zr 0.1 O 2 on which the CO 2 conversion reached theoretical equilibrium value as high as 98.2% with the methane selectivity of 100% at a reaction temperature as low as 230 °C. Moreover, there was almost no deactivation for the 3Ru-30Ni/Ce 0.9 Zr 0.1 O 2 catalyst during 300 h at 230 °C indicating excellent catalytic stability and coke resistence ability. It was also found that the low-temperature activity of 3Ru-30Ni/Ce 0.9 Z r0.1 O 2 catalyst prepared by one-pot hydrolysis method was much higher than the one prepared by impregnation method. [ABSTRACT FROM AUTHOR]

Creep properties of a 4th generation nickel-based single crystal superalloy (Ni-SX) are investigated at 1150 °C and 1100 °C. Fracture mechanism is revealed as competitive microcrack initiation induced by topologically close-packed (TCP) phase formation and creep inconsistency on dendritic structures showing the strong temperature-and-time dependent relations. At 1150 °C, alloy displays the high nucleation rate of TCP phases. Dense TCP particles dissolve the surrounding γ/γ' microstructures forming large depleted zone where is easily stress-concentrated. Dislocations are found to emit from the interface between TCP and depleted zone that promotes dislocation shearing and microcrack initiation in the large depleted zone, as well as the fracture of alloy. On contrary, alloy crept at 1100 °C suffers to relatively restricted TCP nucleation. But the longer creep time gives to larger size of TCP precipitates. Compared to alloy crept at 1150 °C, the depleted zone is much smaller that is not prone for stress concentration. For this creep inconsistency induced by dendritic segregation plays the main role in determining the creep properties. The larger local strain rate forms microcracks primarily in interdendritic region causing the final fracture. • Creep behaviors of a new 4th generation Ni-SX are compared at 1150 °C and 1100 °C. • Temperature-and-time dependent TCP precipitation and creep inconsistency affect the creep. • Depending on temperature, the two factors display competitive behaviors. • Higher temperature of 1150 °C enlarges the influence of TCP precipitation. • Creep inconsistency on dendritic structures dominants the creep at 1100 °C. [ABSTRACT FROM AUTHOR]

• The optimal critical value with (0.1, 0.1) of the envelope is determined in linear-damage-summation method. • Prediction accuracy of parameters at characteristic cycle with physical meaning is the highest. • Evolution of creep damage based on time fraction, simple ductility exhaustion, and strain-energy-density exhaustion. • Prediction of energy-life model based on damage mechanisms and frequency-correction. The purposes of the present work are to evaluate the prediction accuracy of characteristic cycle on creep-fatigue life prediction and to analyze the advantages and disadvantages of various models in tensile strain-dwell tests. The parameters of the first cycle, the 10% life, the half-life, and the characteristic cycle that we proposed (a turning point between the initial rapid softening and subsequent slight softening/hardening) are employed to linear-damage-summation (LDS) and energy-life prediction models based on the creep-fatigue data of directionally-solidified Nickel-based superalloy, DZ445, at 900 °C. It is found that the characteristic cycle parameters with clear physical significance have the highest life prediction accuracy. Moreover, the optimal critical value of fatigue and creep damage (the coordinate of the creep-fatigue envelope intersection) in the LDS is also determined. The prediction accuracy of creep damage based on the time-fraction, the simple ductility-exhaustion, and the strain-energy- density-exhaustion models is sequentially improved in the LDS rule. In the energy-life model, the life prediction accuracy based on damage mechanism and frequency correction is higher than the value without any correction. This investigation provides a new method of the parameter-selection for the creep-fatigue life prediction, which is accurate and convenient. It provides the theoretical-guidance for creep-fatigue life prediction in both laboratory experiment and actual components. [ABSTRACT FROM AUTHOR]

• Fatigue life with dwell time is explained by mechanical response and damage mechanism. • Inelastic strain range, stress relaxation, mean stress, and hysteresis loop with dwell time. • Schematic illustration of fracture and deformation mechanism with dwell time. • Energy-life prediction model for the creep-fatigue data with high strain range. High total strain-controlled creep-fatigue tests of 1.8% were performed for a directionally-solidified Ni-based superalloy, DZ445, at 900 °C in air. Dwell times of 0, 2, and 5 min. were introduced at the tensile peak strain for each cycle. Experimental results show a decrease in fatigue life with increasing dwell time. The significant cyclic softening is observed after the application of the dwell time. The mean compressive stress and large plastic-strain accumulation are produced due to the stress relaxation in the tensile-dwell period, resulting in the increase of the hysteresis loop area. The typical single-source crack-initiation and transgranular crack-propagation are transformed into multi-source crack-initiation and mixed transgranular and intergranular crack-propagation mode by these characteristics. Dislocation features are transformed from cutting of γ' precipitates by multiple stacking faults to the mixed mode of dislocation climbing and slipping. The reduction in the fatigue life with increasing the dwell time is well explained on the basis of the mechanical response and damage mechanism. The fatigue life is also predicted by the energy-based life-prediction model. [ABSTRACT FROM AUTHOR]