Non-Traditional Machining

15 flashcards · Other · by Liam Kehoe

1. Laser beam machining NTM

   Highly focused optical energy High density energy melts and evaporates

2. Pros and Cons of Laser/EBM

   Pros Can process very small features Very accurate Cons (EBM) Expensive Limited workpiece size Require vacuum

3. Electron beam NTM

   Produces X-rays Requires vacuum

4. EDM Pros and Cons

   Pros Minimal forces Delicate components Cons Limited for electrically conducting workpiece Slow Electrode wear Shaped electrodes

5. Electrical-Discharge Machining (EDM)

   Spark erosion machining Arc is produced and removes materials Very common for delicate components When a voltage is applied to the tool, a magnetic field causes suspended particle in dielectric fluid to concentrate and form bridge for current to flow to the workpiece

6. Chemical NTM Cons

   Requires masks Can be expensive Under cut Environmental concerns

7. Chemical NTM Pros

   Process layered materials Deburring process Can process very hard materials Batch process

8. Electrochemical Machining (ECM)

   Reverse of electroplating Shape tool is made of brass, copper, bronze or SS Electrolyte is a highly conductive inorganic salt solution Often used for nickel-based aerospace components

9. Chemical Machining NTM

   Remove materials by chemical dissolution using etchant Often used for deburring process Not environmental friendly

10. Cons of mechanical NTM

    Hard to control the depth of cut Not as accurate compared to conventional machining

11. Pros of mechanical NTM

    Can process any materials (hard and brittle, soft) No heat No deflection

12. Abrasive water jet

    Act as saw Commonly used for variety of materials including food and fabric processing No heat is produced, no deflection Powders are mixed Difficult to control depth of cut

13. Ultrasonic NTM

    Material is removed by micro chipping or erosion with abrasive particles Grains are in a water slurry Best suited for hard and brittle materials

14. Types of NTM

    Mechanical - erosion of work piece by high velocity stream of abrasives and fluid Chemical - chemical etchants selective (require masks) Electrical/Thermal - energy applied to a small portion of workpiece by vaporization Laser and EBM

15. Why use non-traditional machining

    Strength and hardness of the workpiece material are very high Too brittle Too flexible or too slender The shape of the part is complex Special surface finish and dimensional tolerance requirements The temperature rise during processing and residual stresses developed in the workpiece