Cutting processing cutting tool, cut the blank or redundant material layer on the workpiece, workpiece get rules of geometric shape, size and surface quality of machining method.

Any machining must meet three basic conditions: cutting tool, workpiece and cutting movement. Cutting tools should be edge, the material must be hard than the workpiece; Different forms of cutting tool structure and cutting movement, constitute a different cutting method. The blade and the number of blade are fixed method for cutting tool turning, drilling, boring, milling, planing, broaching, and cutting, etc.; The blade and the number of blade is not fixed abrasive and abrasive for cutting method of grinding, grinding, honing and polishing.

Machining is the main processing methods in mechanical manufacturing. Although blank continuously improve manufacturing precision, precision casting, precision forging, extrusion, powder metallurgy and other processing technology, widely used, but due to the machining of the adaptation scope is wide, and can achieve high precision and low surface roughness, still occupies an important position in the mechanical manufacturing process.

Machining history can be traced back to primitive people created stone chopping, bone drill labor tools such as the paleolithic period. In China, as early as the shang dynasty medium-term (13th century BC), already can use grinding method processing bronze mirror; The late shang dynasty (the 12th century BC), was bit in bronze of the bone hole; Western han dynasty (BC 206 ~ 23), has been using screw drill and drill pipe, with the method of the sand grinding in "that" more than 4000 piece of jade hard, drilling more than 18000 1 ~ 2 mm diameter hole.

The middle of the 17th century, the Chinese began to make use of animal instead of human driver tool for machining. Such as AD 1668, was in the draft power driven device, tooth cutter milling on the astronomical instrument with multiple large diameter two zhangs (ancient zhangs) copper ring, and then use stone for finish machining.

18 century, the British industrial revolution began, with the invention of the steam engine and the modern machine tools, machining with the steam engine as power; In the 1870 s, in the machining and started to use electric power.

Principles of metal cutting research began in the 1850 s, the study of the principle of the grinding began in the 1880 s, then there appeared a variety of new cutting tool materials. Appeared in the late 19th century of high speed steel cutter, cutter permissible cutting speeds than carbon tool steel and alloy tool steel cutter increased by more than double, to around 25 m/min; 1923 carbide cutting tools, about two times higher than that of high speed steel cutting tools and cutting speed; After the 30 s of ceramic metal and superhard materials (synthetic diamond and cubic boron nitride), to further improve the cutting speed and processing accuracy.

With the continuous development of machine tools and cutting tools, machining accuracy, efficiency, and constantly improve the automatic degree and the range of application is expanding, which greatly promoted the development of modern machinery manufacturing.

Metal material cutting processing, there are many classification methods, common are according to the technological characteristics, according to the material removal rate and machining accuracy, according to the surface of the molding method of three kinds of classification methods.

Machining process characteristics depend on the structure of cutting tool, and the relative motion of cutting tool and the workpiece. So according to the process characteristics, machining can generally be divided into: turning, milling, drilling, boring, ream, cutting, slotting, broaching, sawing, grinding, grinding, honing, super finishing, polishing, gear, worm gear processing, thread machining, ultra precision machining, fitter and scraping.

According to the material removal rate and machining accuracy, cutting processing can be divided into the roughing and semi-finishing and finishing, finishing processing, modified processing, ultra-precision machining and so on.

Rough machining is to use large cutting depth, by one or a few knife, cut off from the workpiece most or all of the processing method of machining allowance, such as coarse, rough plane, rough milling, drilling and cutting and rough machining of high efficiency but low precision, generally used as a pre-process; Semi-finishing general for intermediate process between roughing and finishing; Finishing is made of fine cutting way, make the machining surface to achieve high precision and surface quality, such as car, plane, hinge, such as fine grinding, finish machining in general is the final processing.

Finishing machining is carried out after finish machining, the goal is to get a smaller surface roughness, and slightly improved accuracy. Finishing machining of small machining allowance, such as honing, grinding and super precision grinding and super finishing, etc.; Modification process in order to reduce the surface roughness, in order to improve the corrosion, dust, and to improve the appearance, not demanding higher precision, such as polishing, sanding, etc; Ultra-precision machining is mainly used in aerospace, laser, electronics, nuclear power and other need some special precision parts processing, the accuracy can reach above IT4, such as turning, mirror mirror grinding, soft grinding grain of chemical mechanical polishing, etc.

The workpiece when machining is processing surface depend on the relative motion in terms of the cutting tool and workpiece. According to surface formation method, cutting processing can be divided into the tip trajectory, forming cutting tools and generating method.

Point locus method depend on the tip trajectory relative to the workpiece surface, to obtain the required surface workpiece geometry, such as cylindrical turning, planing, flat, cylindrical grinding, by copying turning forming surface, such as the tip trajectory depends on machine tools provided by the relative motion of cutting tool and the workpiece;

Forming cutter method referred to as "forming method, is to use match the end surface of the workpiece contour forming tool, or forming grinding wheel processing forming surface, such as forming milling and turning, forming forming grinding, because of the forming tool manufacturing is more difficult, so generally used only for processing the short forming surface;

Generating method is also called the generating cutting, is the process of cutting tool and the workpiece relative generative movement, cutting tool and workpiece in the instantaneous center line for pure roll, keep certain ratio between relations, gained by the processing surface is the blade in the envelope of the movement and processing of gear hobbing, gear shaper, gear shaving and gear honing and gear grinding are generating method for processing. Some machining both point locus method and characteristics of the forming method of cutting tool, such as thread cutting.

Machining quality mainly refers to the workpiece machining accuracy and surface quality (including surface roughness, residual stress and surface hardening). With the progress of technology, the machining quality enhances unceasingly. In the late 18th century, machining accuracy in mm; The beginning of the 20th century, the machining precision of the highest reached 0.01 mm; To the 50 s, machining accuracy up to micron level; In the 70 s, the machining accuracy and increased to 0.1 micron.

The main factors influencing the machining quality of machine tool, cutting tool, fixture, workpiece blank, process method and the processing environment, etc. To improve the quality of machining, must take appropriate measures to aspects of the work such as reducing machine tool error, correct selection cutting tools, improve the quality of blank, reasonable arrangement of process and improve the environmental conditions, etc.

Improve the cutting parameter in order to improve the material removal rate, is the basic way to improve machining efficiency. Commonly used efficient machining method has high speed cutting, strong cutting, plasma arc heating cutting, vibration cutting, etc.

In more than 45 m/s cutting grinding speed is called high speed grinding. Using high speed cutting or grinding can improve efficiency, but also reduce the surface roughness. High-speed cutting or grinding requirements machine tools with high speed, high rigidity, high power and good vibration resistance process system; Request knife has a reasonable geometry parameter and convenient way of fastening, also should be considered safe and reliable method of chip breaker.

Strong cutting refers to the large feed or large cutting depth of cutting, generally used for cutting and grinding. Powerful turning tool is the main characteristics in addition to the main cutting edge, there is a parallel to the vice cutting edges on the surface of the workpiece machined involved in cutting at the same time, it can increase the feeding than ordinary turning several times or even dozens of times. Compared with the high speed cutting, cutting cutting temperature is low, a longer tool life and cutting efficiency is high; Defect is processing surface is rough. Cutting force, the radial cutting force is very big so it is not suitable for machining long workpiece.

Vibration cutting is along the tool feed direction and additional low frequency or high frequency vibration cutting, can improve the cutting efficiency. Low frequency vibration cutting has the very good effect of chip breaker, the chip can not break, make the blade strength increases, the total power consumption when the cutting than ordinary cutting device with a chip breaker to reduce 40%. High frequency vibration cutting is also called ultrasonic vibration cutting, helps to reduce friction between cutter and workpiece, and reduce the cutting temperature, reduce the adhesion wear on the tool, so as to improve cutting efficiency and machining surface quality and tool life can increase about 40%.

For wood, plastic, rubber, glass, marble, granite and other non-metallic materials of cutting processing, is similar to the cutting metal materials, but the tools, equipment and cutting dosages, etc have different features.

Wood products machining mainly in all kinds of woodworking machine, its methods mainly include: cutting, plane cutting, turning, milling, drilling, sanding, etc.

Rigidity of plastic than metal is poor, easy bending deformation, especially thermoplastics poor thermal conductivity, easy to heat up to soften. So when cutting plastic, appropriate USES high speed steel and carbide cutting tools, select small feeding and cutting speed, high using compressed air to cool. If a sharp tool, right Angle, can produce continuous chip, is easy to take away heat.

Glass (include the semiconductor materials such as germanium and silicon) of high hardness and brittleness. Commonly used for glass cutting cutting, drilling, grinding and polishing method. Under 3 mm of thickness of glass, the most simple cutting method is to use the diamond or other hard substance, the score by hand on the glass surface, using indentation place of stress concentration, can be broken by hand.

For marble, granite, concrete and other hard materials processing, mainly used for cutting, turning, drilling, planing, grinding and polishing method. Available when cutting circular saw blade with abrasive and water; Cylindrical and end face can be used cemented carbide cutting tool rake Angle, cutting speed by 10 ~ 30 m/points turning; Drilling can use carbide drill; Big stone flat available hard alloy cutter or roll cutting plane; Precision, smooth surface, can use three pieces of each datum to research the method, or method of grinding and polishing.