The grain growth and thermal stability of nanocrystalline Ni-TiO2composites were systematically investigated.Thenanocrystalline Ni-TiO2composites with different contents of TiO2were prepared via electroplating method ...The grain growth and thermal stability of nanocrystalline Ni-TiO2composites were systematically investigated.Thenanocrystalline Ni-TiO2composites with different contents of TiO2were prepared via electroplating method with the variation ofTiO2nano-particles concentration.The effect of TiO2content on the grain size,phase structure and microhardness was investigatedin detail.The corresponding grain growth and diffusion mechanisms during the heating process were also discussed.The optimalmicrohardness of HV50270was achieved for the composite with addition of20g/L TiO2nano-particles after annealing at400°C for90min.The calculation of the activation energy indicated that lattice diffusion dominated at high temperatures for thenanocrystalline Ni-TiO2composites.It was indicated that the increase of TiO2nano-particles content took effect on restricting thegrain growth at high temperatures by increasing the grain growth activation energy.展开更多
基金Project(51401024)supported by the National Natural Science Foundation of ChinaProject(20150942006)supported by Basic Research Program of Beijing Institute of Technology,China
文摘The grain growth and thermal stability of nanocrystalline Ni-TiO2composites were systematically investigated.Thenanocrystalline Ni-TiO2composites with different contents of TiO2were prepared via electroplating method with the variation ofTiO2nano-particles concentration.The effect of TiO2content on the grain size,phase structure and microhardness was investigatedin detail.The corresponding grain growth and diffusion mechanisms during the heating process were also discussed.The optimalmicrohardness of HV50270was achieved for the composite with addition of20g/L TiO2nano-particles after annealing at400°C for90min.The calculation of the activation energy indicated that lattice diffusion dominated at high temperatures for thenanocrystalline Ni-TiO2composites.It was indicated that the increase of TiO2nano-particles content took effect on restricting thegrain growth at high temperatures by increasing the grain growth activation energy.
