1. Abrasive Jet Machining

3. Mixing chamber vibrates at 50 Hz

4. Abrasive velocity 150 to 300 m/s

5. Aluminum or Silicon carbide abrasive grains contained in gas or air – for heavy cleaning

6. Magnesium carbonate for light cleaning

8. Aluminum oxide and silicon carbide- cleaning, cutting, and debarring

9. Magnesium carbonate – light cleaning and etching

10. Sodium bicarbonate – fine cleaning and cutting of soft material

11. Glass beads – Polishing and de-flashing

12. Foundry Sand (Garnet is 30% more effective than sand)

13. Size of abrasives range from 10 to 50 micrometer

14. Powders should be free from silica dust which is hazardous

18. AWJM cuts 10 times faster than the conventional machining methods of composite materials

20. The Machining System The basic machining system of AWJM incorporates the following elements: Water delivery Abrasive hopper and feeder Intensifier Filters Mixing chamber Cutting nozzles Catcher

21. Processing Parameters

23. Mixing of water and abrasives limits the minimum jet diameter that can be used

24. Abrasives are replaced by ICE

25. Low MRR compared to AWJM, however economy and environmental impact is high

27. Abrasive jet do not heat your part therefore no thermal distortion or hardening of material

28. Much faster than EDM

30. Jet velocity 100-350 m/s

32. For metals MRR range from 1.6-4.1 mm3/min

34. Engraving

35. De-burring on metals and plastics

36. Frosting glass

37. Cutting intricate pattern in hard and brittle materials

38. Cleaning oxides from metal surfaces

39. Cleaning and trimming of electronic components

40. Removing smudges and films from documents and museum artifacts

41. Machining of superhard materials

43. Deburring of cross holes, slots, and threads in small precision parts that require a burr-free finish, such as hydraulic valves, aircraft fuel systems, and medical appliances

44. Machining intricate shapes or holes in sensitive, brittle, thin, or difficult-to-machine materials

45. Insulation stripping and wire cleaning without affecting the conductor

46. Micro-deburring of hypodermic needles

47. Frosting glass and trimming of circuit boards, hybrid circuit resistors, capacitors, silicon, and gallium

49. The process is used for machining superalloys and refractory materials.

50. It is not reactive with any workpiece material.

51. No tool changes are required.

52. Intricate parts of sharp corners can be machined.

53. The machined materials do not experience hardening.

54. No initial hole is required for starting the operation as required by wire EDM.

55. Material utilization is high.

57. Stray cutting can’t be avoided

58. The tapering effect may occur especially when drilling in metals.

59. The abrasive may get impeded in the work surface

60. Suitable dust-collecting systems should be provided

61. Soft materials can’t be machined by the process

62. Silica dust may be a health hazard

65. As the tool is not shaped to conform to the produced feature, it is mainly for cutting or slitting or drilling and not for profiling or surface generation.

66. It is however used for polishing and etching. Very low MRR in polishing, i.e., < 0.015 cm3/min.

68. Water Jet Machining MACH-3 Velocity The hydraulic pump is powered from a 30- kilowatt (kW) electric motor and supplies oil at pressures as high as 117 bars in order to drive a reciprocating plunger pump termed an intensifier (4 bar to 3800 bar).

69. Water Jet Machining The accumulator maintains the continuous flow of the high- pressure water and eliminates pressure fluctuations. It relies on the compressibility of water (12 percent at 3800 bar) in order to maintain a uniform discharge pressure and water jet velocity, when the intensifier piston changes its direction.

70. Processing Parameters

71. Operating Summary Fluid Type : Water or water with additives Additive : Glycerin, Polyethylene Oxide or long chain polymer Pressure : 100 to 1000 MPa Jet Velocity : 300 to 1000 m/min Power : Up to 40 Kw Metal Removal Rate : 0.5 mm3/s for metals and alloys, 20 mm3/s for Elastomers Nozzle Material : Hardened steel, WC synthetic sapphire

72. Water Jet Cutting Rates

74. No heat is produced.

75. Cuts can be started at any location without the need for predrilled holes.

76. Wetting of the workpiece material is minimal.

77. There is no deflection to the rest of the workpiece.

78. The burr produced is minimal.

79. The tool does not wear and, therefore, does not need sharpening.

80. The process is environmentally safe.

82. Simple fixturing eliminates costly and complicated tooling, which reduces turnaround time and lowers the cost.

83. Grinding and polishing are eliminated, reducing secondary operation costs.

84. The narrow kerf allows tight nesting when multiple parts are cut from a single blank.

85. It is ideal for roughing out material for near net shape.

86. It is ideal for laser reflective materials such as copper and aluminum.

87. It allows for more accurate cutting of soft material.

89. Stray cutting

90. Abrasive particles embedding