鋁(lv)(lv)合金(jin)(jin)(jin)強度和硬度相對(dui)較(jiao)低、對(dui)刀(dao)具磨損小，且熱(re)導率較(jiao)高(gao)，使(shi)切(qie)削(xue)(xue)(xue)溫度較(jiao)低，所以鋁(lv)(lv)合金(jin)(jin)(jin)的切(qie)削(xue)(xue)(xue)加(jia)(jia)工(gong)(gong)性(xing)較(jiao)好(hao)，屬于易(yi)加(jia)(jia)工(gong)(gong)材料，適于較(jiao)高(gao)切(qie)削(xue)(xue)(xue)速度切(qie)削(xue)(xue)(xue)。高(gao)速鉆(zhan)削(xue)(xue)(xue)時(shi)主軸的轉速通(tong)常在10000r/min 以上(shang)。但是，鋁(lv)(lv)合金(jin)(jin)(jin)熔點(dian)較(jiao)低，溫度升高(gao)后塑性(xing)增大，在高(gao)溫高(gao)壓作用下(xia)，切(qie)屑(xie)界面(mian)摩擦(ca)力很大，切(qie)屑(xie)易(yi)熔結(jie)在刀(dao)刃上(shang)而(er)粘(zhan)刀(dao)。熔結(jie)物被后續加(jia)(jia)工(gong)(gong)沖擊脫(tuo)落時(shi)也會造(zao)成刀(dao)刃缺損。鋁(lv)(lv)合金(jin)(jin)(jin)的上(shang)述切(qie)削(xue)(xue)(xue)加(jia)(jia)工(gong)(gong)性(xing)使(shi)得其微小孔鉆(zhan)削(xue)(xue)(xue)加(jia)(jia)工(gong)(gong)存在諸多(duo)工(gong)(gong)藝(yi)難點(dian)。這(zhe)是因為，鉆(zhan)削(xue)(xue)(xue)加(jia)(jia)工(gong)(gong)是切(qie)削(xue)(xue)(xue)條(tiao)(tiao)件(jian)最惡劣的加(jia)(jia)工(gong)(gong)方法(fa)之一，而(er)鉆(zhan)削(xue)(xue)(xue)小孔，尤其是直徑1mm及以下(xia)的小孔，不但集(ji)中了鉆(zhan)削(xue)(xue)(xue)加(jia)(jia)工(gong)(gong)的全部(bu)難點(dian)，而(er)且切(qie)削(xue)(xue)(xue)條(tiao)(tiao)件(jian)較(jiao)普通(tong)孔徑鉆(zhan)削(xue)(xue)(xue)更為惡劣。具體(ti)(ti)體(ti)(ti)現在兩個方面(mian)：

（1）微小(xiao)鉆(zhan)頭的(de)剛度隨孔徑的(de)減小(xiao)和鉆(zhan)孔長度比的(de)增(zeng)加(jia)而急劇(ju)下降(jiang)。

（2）麻花鉆(zhan)頭屬于(yu)結構形狀比較(jiao)(jiao)復(fu)雜的刀具，為減輕(qing)導向(xiang)(xiang)部分與(yu)孔壁(bi)的摩擦(ca)，標準麻花鉆(zhan)在導向(xiang)(xiang)部分制(zhi)有較(jiao)(jiao)窄的棱邊，而且從外圓向(xiang)(xiang)尾(wei)部制(zhi)成倒錐(zhui)，形成較(jiao)(jiao)窄的副(fu)后刃面和(he)大(da)于(yu)0°的副(fu)偏刃角(jiao)。

由(you)于自身結構的(de)缺陷和微(wei)(wei)小(xiao)孔鉆(zhan)(zhan)(zhan)(zhan)削的(de)惡劣工(gong)(gong)藝條件(jian)，微(wei)(wei)小(xiao)麻花鉆(zhan)(zhan)(zhan)(zhan)應用(yong)(yong)于鋁合金(jin)微(wei)(wei)小(xiao)孔加(jia)工(gong)(gong)時，鉆(zhan)(zhan)(zhan)(zhan)偏、粘(zhan)刀(dao)、切屑堵塞、纏繞等問題經(jing)常(chang)(chang)造成鉆(zhan)(zhan)(zhan)(zhan)頭(tou)(tou)折斷，而且折斷部分(fen)很難從工(gong)(gong)件(jian)中取出，常(chang)(chang)以(yi)工(gong)(gong)件(jian)報廢(fei)而告終。微(wei)(wei)小(xiao)鉆(zhan)(zhan)(zhan)(zhan)頭(tou)(tou)壽命(ming)(ming)的(de)分(fen)散性極(ji)(ji)大，因此(ci)在(zai)(zai)許多情況下，特別是(shi)在(zai)(zai)鉆(zhan)(zhan)(zhan)(zhan)削貴重工(gong)(gong)件(jian)時，不得(de)不在(zai)(zai)遠(yuan)未(wei)達到鉆(zhan)(zhan)(zhan)(zhan)頭(tou)(tou)壽命(ming)(ming)平均值時就將鉆(zhan)(zhan)(zhan)(zhan)頭(tou)(tou)提(ti)前換(huan)掉，造成鉆(zhan)(zhan)(zhan)(zhan)頭(tou)(tou)和輔助工(gong)(gong)時的(de)極(ji)(ji)大浪費(fei)。微(wei)(wei)小(xiao)孔鉆(zhan)(zhan)(zhan)(zhan)削加(jia)工(gong)(gong)中避(bi)免鉆(zhan)(zhan)(zhan)(zhan)頭(tou)(tou)折斷、提(ti)高(gao)鉆(zhan)(zhan)(zhan)(zhan)頭(tou)(tou)壽命(ming)(ming)、保護工(gong)(gong)件(jian)的(de)途徑(jing)主要有2 種(zhong)：一是(shi)針對工(gong)(gong)件(jian)材(cai)料的(de)切削性能(neng)，推薦優化的(de)切削參數(shu)、減少切削力(li)、提(ti)高(gao)鉆(zhan)(zhan)(zhan)(zhan)頭(tou)(tou)耐用(yong)(yong)度。二(er)是(shi)在(zai)(zai)線實時監測鉆(zhan)(zhan)(zhan)(zhan)削過程，在(zai)(zai)達到監測閾(yu)值時預報換(huan)刀(dao)，來(lai)提(ti)高(gao)鉆(zhan)(zhan)(zhan)(zhan)頭(tou)(tou)利用(yong)(yong)率。