常圧焼結窒化けい素セラミックスの高温動クリープ

概要

論文の詳細を見る
Dynamic creep tests were performed for the specimen with projections of sintered silicon nitride ceramics at test temperature, T=1300℃, where triangular stress wave was imposed at stress rates σ=0.1,0.5 and 20 MPa/s. Then dynamic creep displacement was measured between the two projections by means of the laser beam type displacement measuring system. Cyclic strain range decreased monotonously with increase in the number of stress cycles in dynamic creep test and this attenuation was much more enhanced at the higher cyclic stress, suggesting that cyclic deformation resistance increases during dynamic creep at 1300℃. The equivalent stresses σ_<ep.1> and σ_<ep.2> were assessed to examine the relationships between the dynamic and static creep strain rates, and the dynamic and static creep life times to failure. Then minimum creep strain rate ε_<cmln> and creep life time to failure t_f were plotted against the equivalent stresses in the dynamic creep. It was shown that the relationships between ε_<cmln> and σ_<ep.1>, and t_f, and σ_<ep.2> were in quite good agreement with those in the static creep.
一般社団法人日本機械学会の論文
1999-03-25