Abstract: Using 12mm diameter solid carbide straight end mills with TiAlN coating, a P20 steel at 41HRC was machined in the milling speed range of 151 to 942 m/min. The morphology of the chips and the milling forces at various speeds were investigated. Chips are found to be continuous at 151 to 650 m/min. The saw-tooth chips are formed at 754 to 942 m/min. The forces increase with the increasing of milling speeds. They increase to maximum when the milling speed approaches to the critical value. After the speed, the increases of the milling speeds cause decreases of the cutting forces. Furthermore, based on chip formation theory at high speed machining, the effect of milling speed on milling forces were investigated.

Key words: milling force, saw-tooth chip, high speed end milling, hardened steel

摘要：

使用直径为12mm的TiAlN涂层整体圆柱立铣刀，以151～942m/min的切削速度，对硬度为HRC41的P20淬硬钢进行了高速铣削试验，考察了各种切削速度下的切屑形态和切削力。切削速度为151～650m/min时，形成带状切屑；切削速度为754～942m/min时，形成锯齿形切屑。切削力随切削速度的增大而增大，当切削速度增大到某一临界值，切削力达到最大，此后，随切削速度的继续增大，切削力减小。基于高速切削变形理论，分析了切削速度对切削力的影响规律。

关键词: 切削力, 锯齿形切屑, 高速端铣, 淬硬钢