The lumber of Eucalyptus urophylla×E. camaldulensis was heat-treated at either 180, 190, 200, or 210 ºC for 3 h. According to the national forestry standard methods for evaluating the machining properties of lumber, the machining properties (including planing, sanding, boring, mortising, shaping, and turning) of heat-treated and untreated control samples were investigated. The results indicated that the machining properties of the lumbers were improved after heat treatment. In the machining comprehensive evaluation system (top score is 10 points), the scores of the control and heat-treated samples at 180, 190, 200, and 210 ºC were 4.74, 7.76, 8.08, 7.46, and 6.96 points, respectively. A temperature of 190 ºC was thus optimal for the comprehensive machining properties when heat-treatment was used to modify the machinability of E. urophylla×E. camaldulensis wood.

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Summary Mechanical stress which develops during redox or creep of nickel‐doped yttria‐stabilized zirconia (Ni‐YSZ) anode has been widely recognized as an important limitation for structural stability and commercialization of solid oxide fuel cell (SOFC). In this paper, the cooperative effect of reoxidation after creep (termed creep reoxidation) arising from abnormal operation condition on the mechanical robustness of SOFC is studied. In order to simulate inhomogeneous oxidation of Ni‐YSZ at operation temperature, a continuously gradient model with gradients in material properties and local swelling induced by reoxidation is proposed. The stress level, oxidation tolerance, and curvature changes of a half cell undergoing reoxidation after various creep durations are compared. The present study highlights that the stress relaxation due to the creep of anode cermet in operation leads to a higher stress in electrolyte and a lower oxidation tolerance of the cell during the subsequent oxidation stage.

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