A.屈服強(qiáng)度B.強(qiáng)度極限C.疲勞極限D.持久疲勞極限
A.r=0B.r=+0.5C.r=-1D.r=-0.5
A.對(duì)稱循環(huán)應(yīng)力B.非對(duì)稱循環(huán)應(yīng)力C.隨機(jī)變應(yīng)力D.脈動(dòng)循環(huán)應(yīng)力