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As a critical technology, thermal barrier coatings (TBC) have been used in both aero engines and industrial gas turbines for a few decades, however, the most commonly used MCrAlY bond coats which control air plasma sprayed (APS) TBC lifetime are still deposited by the powders developed in 1980s. This motivates a reconsideration of development of MCrAlY at a fundamental level to understand why the huge efforts in the past three decades has so little impact on industrial application of MCrAlY alloys. Detailed examination of crack trajectories of thermally cycled samples and statistic image analyses of fracture surface of APS TBCs confirmed that APS TBCs predominately fails in top coat. Cracks initiate and propagate along splat boundaries next to interface area. TBC lifetime can be increased by either increasing top coat fracture strength (strain tolerance) or reducing the tensile stress in top coat or both. By focusing on the reduction of tensile stress in top coats, three new bond coat alloys have been designed and developed, and the significant progress in TBC lifetime have been achieved by using new alloys. Extremely high thermal cycle lifetime is attributed to the unique properties of new alloys, such as remarkably lower coefficient of thermal expansion (CTE) and weight fraction of β phase, absence of mixed / spinel oxides, and TGO self repair ability, which cannot be achieved by the existed MCrAlY alloys.

Based on the endogenous factors which can affect the strategy of international R&amp, D of China&rsquo, s enterprises, an analysis is carried out on the relationship between market- and technology-orientation of the strategy and the intensity of international R&amp, D. In addition, the mediation effects of innovation capacity endowment are discussed. On this basis, 254 listed enterprises with overseas R&amp, D institutions approved by the Ministry of Commerce of China were taken as the sample for survey administration. The poisson regression method was adopted to test the hypotheses. Additionally, we utilized the Bootstrap method to confirm the robustness of the regression models. Results show that for Chinese enterprises with significant international R&amp, D strategy intentions, market orientation has a significant inhibitory effect on their international R&amp, D intensity, while the technology orientation has a significant stimulating effect on international R&amp, D. In addition, innovation capacity has a significant positive impact on the intensity of international R&amp, D, and plays a partial mediating role in the relationship between technology orientation and international R&amp, D. Therefore, to promote international R&amp, D strategies in the era of high-quality economic development, Chinese enterprises are suggested to establish an innovation-oriented strategy orientation to promote innovation cultural heritage, and to strengthen the accumulation of innovative resources and capabilities.