The yttraluminizing coating on the Ni-base superalloys has been developed by dipping the specimens in a specially made yttrium-containing slurry as an underlayer and over spraying a Cr-Al slurry as a protective layer,...The yttraluminizing coating on the Ni-base superalloys has been developed by dipping the specimens in a specially made yttrium-containing slurry as an underlayer and over spraying a Cr-Al slurry as a protective layer,then heating to 1060℃ and holding for 1 h under argon atmosphere.Analysis by EPMA showed that the yttrium was concentrated in the intermediate zone of the coating as metallic compound Ni-5Y.After exposure to air up to 1000℃,the oxidation test revealed that the anti-oxidation resistance of the yttraluminizing coating with post-aluminizing is much superior to that with single aluminizing only.展开更多
This work studied possibilities of using lanthanum stearate(LaS t) as an antioxidant in epoxidized natural rubber containing 25 mol.% expoxidation(ENR25) compounds. For comparison purposes, two commercial antioxid...This work studied possibilities of using lanthanum stearate(LaS t) as an antioxidant in epoxidized natural rubber containing 25 mol.% expoxidation(ENR25) compounds. For comparison purposes, two commercial antioxidant 4010 NA and MB were also used. The influence of LaS t, antioxidant 4010 NA and MB on cure characteristics, mechanical properties, crosslink density, hot air aging and thermo-oxidative degradation were studied. The results indicated that the incorporation of LaS t and antioxidants could accelerate the vulcanization of ENR. The ENR vulcanizates with antioxidant MB had better mechanical properties than 4010 NA and LaS t. Compared with antioxidant 4010 NA and MB, the ENR25 vulcanizates with the addition of LaS t exhibited the best hot air aging resistance and thermo-oxidative stability.展开更多
文摘The yttraluminizing coating on the Ni-base superalloys has been developed by dipping the specimens in a specially made yttrium-containing slurry as an underlayer and over spraying a Cr-Al slurry as a protective layer,then heating to 1060℃ and holding for 1 h under argon atmosphere.Analysis by EPMA showed that the yttrium was concentrated in the intermediate zone of the coating as metallic compound Ni-5Y.After exposure to air up to 1000℃,the oxidation test revealed that the anti-oxidation resistance of the yttraluminizing coating with post-aluminizing is much superior to that with single aluminizing only.
基金supported by Natural Science Foundation of Hainan Province(514217)Special Fund for Agro-scientific Research in the Public Interest(201403066)
文摘This work studied possibilities of using lanthanum stearate(LaS t) as an antioxidant in epoxidized natural rubber containing 25 mol.% expoxidation(ENR25) compounds. For comparison purposes, two commercial antioxidant 4010 NA and MB were also used. The influence of LaS t, antioxidant 4010 NA and MB on cure characteristics, mechanical properties, crosslink density, hot air aging and thermo-oxidative degradation were studied. The results indicated that the incorporation of LaS t and antioxidants could accelerate the vulcanization of ENR. The ENR vulcanizates with antioxidant MB had better mechanical properties than 4010 NA and LaS t. Compared with antioxidant 4010 NA and MB, the ENR25 vulcanizates with the addition of LaS t exhibited the best hot air aging resistance and thermo-oxidative stability.