A.15% B.20% C.25% D.30%
A.σa增大,F(xiàn)‘應(yīng)適當(dāng)減小 B.σa增大,F(xiàn)‘應(yīng)適當(dāng)增大 C.σa增小,F(xiàn)‘應(yīng)適當(dāng)減小 D.σa減小,F(xiàn)‘應(yīng)適當(dāng)增大
A.剪切強(qiáng)度 B.彎曲強(qiáng)度 C.抗拉強(qiáng)度 D.扭轉(zhuǎn)強(qiáng)度