Non-Traditional Machining Processes

Types of electrical machining processes

Electrochemical deburring, electrochemical grinding, electrochemical milling frontal, electrochemical milling side wall, electrochemical polishing, shaped tube electrolytic machining.

Types of thermal machining processes

Electron-beam machining, electrical-discharge grinding, electrical-discharge machining finishing, electrical-discharge machining roughing, laser-beam machining, and plasma-beam machining.

Examples of hybrid machining systems

Abrasive machining and electrochemical machining, waterjet cutting and wire EDM, electrochemical machining and electrical discharge machining, laser cutting and punching of sheet metal.

Types of mechanical machine processes

Abrasive-flow machining, low-stress grinding, ultrasonic machining.

Nontraditional machining processes

Are non-mechanical means of material removal.

Removal of Material (not chips)

Chemical machining (CM), electrochemical machining (ECM), electrochemical grinding (ECG), electrical-discharge machining (EDM), wire electrical-discharge machining, laser beam machining (LBM), water-jet machining (WJM), abrasive water-jet machining, abrasive-jet machining (AJM).

Types of advanced machining process as

Chemical machining, Electrochemical machining, electrochemical grinding, electrical-discharge machining, and wire electrical-discharge machining.

Types of Advanced machining

Chemical machining, electrical-discharge machining, electron-beam machining, laser machining, electrochemical machining.

Types of chemical machining processes

Chemical machining, photochemical machining, and electropolishing.

Types of chemical machining

Chemical milling, wet etching, chemical blanking, photochemical blanking.

Electrochemical grinding

Combines electrochemical machining and conventional grinding. The abrasive material on the wheel has a couple of functions. Less than 5% is removed by the abrasives. Suitable for applications similar to those for milling, grinding, and sawing.

Characteristics of electrochemical machining, ECM

Complex shapes with deep cavities, highest rate of material removal among other nontraditional processes, expensive tooling and equipment, high power consumption, medium to high production quantity.

Characteristics of Wire electrical-discharge machining

Contour cutting of flat or curved surfaces, expensive equipment.

Advantages of waterjet machining

Cuts can be started at any location without the need for pre-drilled holes. No heat is produced. No deflection of the rest of the workpiece takes place. Little wetting of the workpiece takes place. The burr produced is minimal. It is an environmentally safe manufacturing operation.

Characteristics of water-jet machining, WJM

Cutting all types of nonmetallic materials, suitable for contour cutting of flexible materials, no thermal damage, noisy.

Characteristics of laser-beam machining, LBM

Cutting and hole making on thin materials, heat- zone, does not require a vacuum, expensive equipment, consumes much energy.

Characteristic of electron-beam machining, EBM

Cutting and hole making on thin materials, very small holes and slots, heat-affected zone, requires a vacuum, expensive equipment.

Characteristics of electrochemical grinding, ECG

Cutting off and sharpening hard materials, such as tungsten-carbide tools, also used as a honing process, higher removal rate than grinding.

Characteristics of abrasive-jet machining, AJM

Cutting, slotting, deburring, etching, and cleaning of metallic and nonmetallic materials; tends to round off sharp edges; can be hazardous

Types of rough cutting

Flame cutting, snagging such as course grinding, and sawing.

Laser microjet

Has a focusing lines, a laser, window, a water chamber, and a nozzle. The laser is guided by water stream.

Electron-beam machining

Has a high-voltage cable, cathode grid, anode, optical viewing system, electron stream, magnetic lens, deflection coils, a viewing port to the vacuum chamber and work piece that is on the worktable, there is a high vacuum pump.

Types of finishing processes

Honing, barrel finishing, electrochemical grinding, grinding, electropolishing, polishing, lapping, superfinishing.

Types of forming

Hot rolling, forging, extruding, cold rolling, cold drawing, roller burnishing.

Abrasive-jet machining

In this type of machining, abrasive particle is propelled at the workpiece surface by a high-velocity jet of dry air, nitrogen, or carbon dioxide. The result is a concentrated force that removes the material.

Electrical-discharge machining

Is based on the erosion of metals by spark discharges. The Dielectric fluid has three functions. The electrodes are usually made up of graphite and are subject to wear.

Chemical machining

Is based on the fact that chemicals can attack and etch most material, removing a small amounts. Carried out by chemical dissolution using reagents or etchants, such as acid and alkaline solutions.

Electrochemical machining

Need to have an electrolyte, anode (+ve) and a cathode (-ve). Depends on the high flow rate of the electrolyte in the tool workpiece gap.

Summary of lecture 21

Nontraditional machining process utilizes chemical, electrochemical, electrical, and high-energy-beams sources of energy. The mechanical properties of the workpiece material is not significant for these types of processes,. Chemical and electoral methods are suitable particularly for hard materials and complex shapes. High-energy-beat machining processes basically utilize laser beams, electron beams, and plasma beams. WJM, AWJM., and AJM processes can be used for cutting as well as deburring operations. Hybrid machining processes offer possibilities for more efficient production of complex parts.

Photochemical blanking

Photographic techniques are used to produce a mask. Chemical machining then follows to produce the blanks.

Types of machining

Planing, shaping, milling, broaching, reaming, turning, boring, drilling.

Types of casting

Sand casting, permanent mold casting, investment casting, die casting.

Masking

Selective attack by the chemical reagant on different areas of the workpiece surface is accomplished by removable layers of the material.

Chemical milling

Shallow cavities are produced on plates, sheets, forgings, and extrusions, generally for the overall reduction of weight.

Characteristics of chemical machining, CM

Shallow removal on large flat or curved surfaces, blanking of thin sheets, low tooling and equipment cost, suitable for low-production runs.

Types of shaped electrolytic Machining operation

Shaped-tube electrolytic machining and electrolytic trepanning.

Characteristics of electrical-discharge machining, EDM

Shaping and cutting complex parts made of hard materials, some surface damage may result, also used as a grinding and cutting process, expensive tooling and equipment.

Characteristics of abrasive water-jet machining, AWJM

Single layer or multilayer cutting of metallic and nonmetallic materials.

Laserbeam machining

The energy source here is a laser, which focuses optical energy on the surface of the workpiece. The highly focused, high density energy source melts and evaporates portions of the workpiece.

Advanced machining processes

The major type of non-traditional machining processes.

Abrasive wet-jet machining

The water-jet contains abrasive particles, which greatly increase the material removal rate.

Important considerations of hybrid machining systems

The workpiece material and its manufacturing characteristics, compatibility of processing parameters across a different processes, cycle times of each individual operation and their synchronization, safety and other considerations.

Waterjet machining

This machining has a fluid supply, a mixer and filter, a pump, an intensifier, an accumulator, a hydraulic unit, controls, a valve, and a sapphire nozzle that the waterjet comes out of towards the workpiece. Under the workpiece is a drain,

Characteristic of laser microjet

Water-jet guided laser uses a 25 to 100 mm diameter stream to mill or cut, large depth of field, little thermal damage from laser machining.

Types of conventional machining processes

Turning and surface grinding.

Wet Etching

When chemical milling is used to fabricate micro electric devices.

Use of nontraditional machining processes

When mechanical methods are not satisfactory, economical, nor even possible due to high strength of work piece material, high hardness of work piece material, workpiece material is too brittle, work piece is too flexible or slender, the part has a complex shape, special surface finish and dimensional tolerance, non-acceptable temperature rise and residual stresses.

Types of electrical-discharge machining

Wire electrical-discharge machining.

Chemical Blanking

used for parts that are otherwise typically produced by mechanical blanking presses from thin plates and foil material. With mechanical presses, vibrations, backlash, and part distortion will make smaller parts difficult to produce