破壊力力学的疲労試験法による窒化ケイ素の疲労き裂伝ぱ挙動の観察

概要

論文の詳細を見る
Fatigue crack propagation tests of silicon nitride were conducted under constant K_<max> and constant stress ratio R using double eccentric pulsating compressive loading at room temperature. The crack propagation rate da/dN could be expressed as a function of K^α_<max>・ΔK^<(1-α)>.However, scatter due to bridging friction was observed in the diagram of da/dN versus K^α_<max>・ΔK^<(1-α)>. The plotting of da/dN against ΔK_<eff> reduced the influence of bridging friction on the expression of crack propagation. Also, the plotting revealed that the crack propagtion under high K_<max> is caused by static fatigue and the propagation under lower K_<max> is by pure fatigue. From these observation, it is suggested that ΔK_<eff> defined as the range of stress intensity factor during crack opening is close to the range of stress intensity factor at crack tip K_<tip>/
一般社団法人日本機械学会の論文
2000-04-25