Difficulty: Easy
Correct Answer: All of these
Explanation:
Introduction / Context:Electrical Discharge Machining (EDM) removes material by controlled spark discharges between an electrode and a conductive workpiece submerged in a dielectric. It is widely used for tooling, dies, and hard alloys that are difficult to machine conventionally.
Given Data / Assumptions:
Concept / Approach:EDM relies on electrical discharges that locally melt and vaporize minute craters; there is no macroscopic cutting force and no mechanical contact. Because hardness does not prevent electrical erosion, EDM readily machines hardened steels and superalloys. With fine finishing pulses and optimized flushing, excellent surface finishes and complex cavities are achievable.
Step-by-Step Solution:
Check hardness capability: EDM is indifferent to mechanical hardness → can machine hardest conductive materials.Check finish/complexity: pulsed control and shaped electrodes allow fine finishes and intricate geometries.Check contact: erosion occurs across a spark gap; there is no mechanical rubbing or cutting.Verification / Alternative check:EDM process descriptions consistently emphasize spark gap control, crater formation, and lack of cutting forces as defining features.
Why Other Options Are Wrong:Choosing any single statement alone underrepresents EDM; all listed statements are concurrently true.
Common Pitfalls:Attempting to EDM non-conductive ceramics; neglecting electrode wear compensation; poor flushing causing arcing and surface damage.
Final Answer:
All of these
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