(1)強(qiáng)化鐵素體 (2)提高鋼的淬透性 (3)提高鋼的回火穩(wěn)定性 (4)形成合金碳化物 (5)阻礙奧氏體的晶粒長(zhǎng)大
A、主俯視圖長(zhǎng)對(duì)正,主左視圖寬相等,俯左視圖立平齊 B、主俯視圖長(zhǎng)對(duì)正,主左視圖高平齊,俯左視圖寬相等 C、主俯視圖立平齊,主左視圖長(zhǎng)對(duì)正,俯左視圖寬相等 D、主俯視圖寬相等,主左視圖長(zhǎng)對(duì)正,俯左視圖立平齊