Basic Machining Operations and Cutting Technology

Basic Machining Operations
Machine tools have evolved from the early foot-powered lathes of the Egyptians and John Wilkinson's boring mill. They are designed to provide rigid support for both the workpiece and the cutting tool and can precisely control their relative positions and the velocity of the tool with respect to the workpiece. Basically, in metal cutting, a sharpened wedge-shaped tool removes a rather narrow strip of metal from the surface of a ductile workpiece in the form of a severely deformed chip. The chip is a waste product that is considerably shorter than the workpiece from which it came but with a corresponding increase in thickness of the uncut chip. The geometrical shape of workpiece depends on the shape of the tool and its path during the machining operation.
基本加工工序和切削技術

機床是從早期的埃及人的腳踏動力車和約翰•威爾金森的鏜床發(fā)展而來的。它們?yōu)楣ぜ偷毒咛峁﹦傂灾尾⒖梢跃_控制它們的相對位置和相對速度。基本上講，金屬切削是指一個磨尖的鍥形工具從有韌性的工件表面上去除一條很窄的金屬。切屑是被廢棄的產(chǎn)品，與其它工件相比切屑較短，但對于未切削部分的厚度有一定的增加。工件表面的幾何形狀取決于刀具的形狀以及加工操作過程中刀具的路徑。